1St night with EW2 sleep all night and did not wake up with a hot flash. Brand new & 1st use Battery dead by the end of use 6:00 pm- 4:30 am. Used sleep mode for cooling thru out the night. I think it works great and I am happy that I purchased this device
@kimmoore0427 thermoelectric Peltier If you apply voltage one way, one side gets hot and the other side gets cold. Reverse the polarity and the hot side turns cold
I have the Wave 1, and was gifted the Wave 2 last Christmas. It charges OK, but every time I need it, it has no charge. Even when it did hold a little bit of a charge, I could never get it to cool, it would only heat, which is the LAST thing I need. I'm so sorry that my late son wasted $300 hard-earned dollars on this, but it's sweet that he was trying to make me more comfortable.
I am really considering buying this. Hot flashes is no joke and i cant deal when they come. I feel like i want to cry so this is something I really might want to try.
Joining in the party here! 🥳I had a forced hysterectomy eight years ago and I am just as miserable today as I was when it happened. I feel like a computer that is short circuiting out when I get an intense flash. They trigger anxiety, ruin my sleep and make me miserable all around. My 70+ y/o mother who entered meno naturally said she maybe had a couple hot flashes and that they weren't intense. I am so jealous, haha.
@@StoneyB I’m glad someone mention anxiety with hot flashes! It’s awful because it’s very hard to go to work feeling like that ! I did get the wave 1 about a year ago! Now on hormone therapy but I’ve got to be honest everyone is different so not all works well until you find the right dose or the right kind of hormone therapy ugh …I’m so sorry and I do understand so very well..please find whatever works to keep from not going crazy !
we all feel like we wanna cry! its disruptive on all levels! no one wants to be in a relationship burning up or at work having to take bathroom breaks as a teacher to cool off. or drinking tons of ice water! from periods to menopause us women donot get a break!
I have a Wave 1 and it’s definitely been useful. I am really hoping for a sleeker form factor in the near future; right now, this doesn’t inspire me to upgrade because it’s just not as big a jump for me from Gen 1 to Gen 2 to make the upgrade worth it. Great review, though!
I have the wave 1 ..it works well for menopause or just being hot or cold..I do the 8 hr mode which comes on and off ..the only thing I don’t like is the band that’s a magnet if you get around metal hold on to yourself lol 😂 but I’m just going to change the band and try it out ..this one looks nice and looks like a watch ..for 299 it is expensive but it was worth the buy! I’m might buy this one as well
well considering all the herbal supplements i've been taking to combat these hot flashes & nights sweats it would have equaled to one of these watches! lol im definetely getting one in a few weeks. i'm sick of being an easy-bake oven!
I have an Embr Wave 2 and I am totally in love with mine. I suffer from horrible hot flashes and I live in Minnesota which is really cold. I sometimes sweat while wearing my heavy duty winter coat can you imagine. It's horrible. But now I have a defense: Embr Wave 🎉🎉🎉🎉🎉
It's a shame these aren't available at discounted rates to anyone who's had hormone related cancer or surgery causing medical menopause, the symptoms of which can be up to 10 times worse than natural menopause! I'd love to get one to try, but way out of my price range sadly. I'm 4 years post breast cancer, left mastectomy and chemo, hot flushes drive me crazy, and I can't take HRT. I'm boiling up just writing this! 🥵
I'm in the same boat as you, but I'm now 7 years out. I purchased this with high hopes, it's been 5 days wearing it and honestly, it doesn't do anything for me. I still get my hot flashes and have to turn on my portable fan. It feels nice to have it on your wrist and I've heard it works for some people, but it hasn't worked for me.
They had me on the strongest mg. prempro there is and it didn't work some ladies are different glad it works for you though some ladies can buy stuff off the shelf and it works me not so lucky
I purchased this item through Amazon in case I needed to return it. So far, I have worn it 5 days and it hasn't done anything for my hot flashes. It feels good on the wrist when the cold waves are coming in, but it doesn't stop the hot flashes and so far, I still get them every 45 minutes. I haven't seen any difference with this, I guess it works for some people and not others. If you buy, make sure you can return in case it doesn't work for you either.
I'm a guy going through radiation for throat cancer and my hot and cold flashes come on pretty intense. Part of this is also from painkillers. I'm constantly taking on and off various layers of clothing. Do you think this would work for me? thanks!❤
As a guy with hot spells due to stress especially at night this device helps a lot. It definitely has a psychological/comforting aspect which is why I would only recommend this device for someone with those types of issues. If you just want a personal heater/cooler you will be disappointed imo
Thanks Erin, I'm seriously considering this as I constantly feel warm even with A/C. I tend to feel 15 degrees warmer than anyone else in the room and don't need a jacket when it's 45 degrees outside and everyone else is bundled up! Do you think this could make a serious difference for me?
God, i so need one of these. I am currently taking a hot flash pill. It works, but obviously wears off over the day. I need something continuous. I am in the process of finding one so I can have it. Never heard of this device until now, which is good they have something like this cause I need it.
H’mm, 😏. I recently bought this item and was very hopeful as I have Hyperhidrosis and suffer frequent hot flushes even though I went through my menopause eighteen years ago. It has recently got worse so I thought I would try this item. The cost was £299.00 but sometimes desperation dictates spending. It does blast your wrist with an immediate cold sensation and says that it pulses a continued cold sensation through your wrist. I can’t say that I agree with this. After the initial blast of cold, I feel nothing and continue to hot flush. Disappointing. I will persevere with it though and just hope, I guess?
I can guarantee you that you only used the 10 minutes hot flash mode turn on the all night hot flash and use it day and night let it chase the hot flashes it will but you have to give it time to work it won't stop the hot flashes it will make them less harsh and stop night sweats and mind disturbances everyone that get no relief from the embrwave 2 is not using it correctly and is expecting not to get hot flashing anymore it help relieve the hot flash quicker and diminish the intensity faster keep at it.
I totally agree with you this should be covered by your insurance I mean women who don't have the means to buy this get hot flashes too So we have to suffer because we're can't afford it. Doesn't seem right to me. I think that if the people who sell this device make it so you can get it through your insurance they would have a lot more sales ( lot's more ) and less Moody females walking around. Think about it for the masses of women who desperately need help with menopause and this device
@@debrawilkins That’s just NOT how the healthcare world works… You should know this… I’m sure this company would LOVE to have insurance pay for this device. But that’s just not up to the manufacturer. It’s ALL ON THE INSURANCE COMPANIES to make that happen, as it is with ALL MEDICAL DEVICES.
If it was to be considered a medical assistance device they would gouge the price up and u would probably still have a huge out of pocket expense. I seen an ad that you can get it for 20 a month
My question is does insurances cover it? Like I can't pay for that price. But I'm early menopause at 38 cause I had a hysterectomy and the hot flashes are killing me. That would help alot but I don't have that kind of money. If my insurance will pay for it sign me up.
They have a subscription plan, you pay $20 a month to use a refurbished device, essentially your renting the device for 20 a month, no contracts, cancel and return anytime. But it's not a rent to own situation
Your thumb is free.!! The solution is the acupressure point in your wrist. This point is found on the inside of the pinkie-finger side of the wrist, about one-half of the width of the thumb back from the wrist crease. Don’t waste your money or time on this device
The Embr wave works it don't stop you from getting hot flashes they will still come but boy when they come the Embr wave deals with them for me I use the all night cooling all day and all night when I use to get a hot flash it was not just heat my body up it was like mood changes going from feeling normal to feeling like my body was being taken over slowly by an alien my head felt like mind worms were slowly boring into my brain as I was having a hot flash then the drenching of sweat would start I would wake up with a drenched pillow that I would have to let dry before making my bed but wow since using Embr wave it's like I have a new life no more drenched pillows I have been waiting to find my pillow drenched but it don't happen any more and those feelings of brain worms don't happen anymore when I get a heat flash I get a very small perspiration on my forehead and it quickly dries up on its own the flash only lasts seconds the Embrwave detects the hot flash and goes after it like a predator and destroys the hot flash I don't care hot much they charge for it it's worth every penny but they were generous enough to only charge 299.00 but I got mind on walmart for 249.00 you can find bargains if you look around I am not being paid for this review I am a captive that was set free of hot flashes by Embrwave I am so grateful to Embrwave.
@@gadgetessa7830 I say this *most respectfully* but that is not necessarily true. I have had a forced hysterectomy due to several cancer diagnosis. Surgical or "forced" hysterectomy can in a lot of cases cause symptoms to come on at a more rapid speed and intense rate than those who enter it naturally. So, yes you are correct in saying the symptoms are the same but the rate & intensity differs. I can attest to extreme symptoms myself and I have been dealing with them for 8 years now. They have not gotten any better in that time. I am not a candidate for any medication since they are all mostly estrogen based and the type of cancer I had has a high rate of reoccurrence with estrogen receptors meaning estrogen could cause a cancer reoccurrence for me.
You just made me buy one for my mumma! Poor thing has been dealing with hot/cold flashes 😢 giving it as an early christmas/birthday gift since it’s a heafty price! Shes been ogling it for a while though… I feel she’s gonna love it.
Yes… It can definitely get in the way in some situation. Certainly easier to take it on and put it off if you are trying to work on a computer. But definitely a factor for folks to consider.
I don’t know what’s inside but it’s like putting an ice cube there. It can get pretty hot when you set it to that mode. I’ve had mine 24 hours an im happy with it. It may not take them away completely yet but it does make it so they don’t peak. Supposed to work better after a week an your body adjusts. It may not work for everyone but it’s like that with anything we use.
It's a peltier device. You can Google them. They're handy little things. It's basically a small electronic heat pump that makes one side cold and the other side hot (it's also what makes portable fridges work). The away facing side must have some kind of heat dissipation for it to work.
It’s still massive and thick. It’s a waste of money!!!! Very good scam. I gave it a good go and it did nothing but warm or cool on my wrist. Must work like magic/ mental for some people. Plus- wearing a smart watch on one arm and this on another looked ridiculous.
I feel like it’s a waste of money. I’d rather just put on a fleece jacket, some hand warmers or grab the electric blanket. Both are much cheaper and will offer much more warmth than this overpriced gimmicky gadget. For people in need of cooling (not us up in the frigid north) a $20 box fan at Walmart or some reusable ice packs would be a better investment.
I'm interested in this to cope with hot flashes caused by prostate cancer treatment. I need something portable that will help when I'm away from home hiking, shopping, etc, when a fan or ice pack is not feasible. I can't anticipate when they'll hit, so a wrist device would be great. If this actually works, I'd consider it money well spent. But I agree that for people who just want to adjust to the current weather, it does seem like a waste of money. And I'm skeptical about it's effectiveness.
A box fan is not really the same I can't waitress carrying around a box fan. I do use ice packs but the new restaurant I work at doesn't even have a freezer.
1St night with EW2 sleep all night and did not wake up with a hot flash. Brand new & 1st use Battery dead by the end of use 6:00 pm- 4:30 am. Used sleep mode for cooling thru out the night. I think it works great and I am happy that I purchased this device
That's great!
@@ErinLawrenceTVwhat exactly makes it turn cold? Just curious
@kimmoore0427 thermoelectric Peltier
If you apply voltage one way, one side gets hot and the other side gets cold. Reverse the polarity and the hot side turns cold
I have the Wave 1, and was gifted the Wave 2 last Christmas. It charges OK, but every time I need it, it has no charge. Even when it did hold a little bit of a charge, I could never get it to cool, it would only heat, which is the LAST thing I need. I'm so sorry that my late son wasted $300 hard-earned dollars on this, but it's sweet that he was trying to make me more comfortable.
I'm sorry to hear that.
You might need a new charger.. write to them.. see what they will do for you.. mine lasts all night plus..
And there’s a 30 day guarantee.. worse case, ship it back..
I am really considering buying this. Hot flashes is no joke and i cant deal when they come. I feel like i want to cry so this is something I really might want to try.
You should!
Joining in the party here! 🥳I had a forced hysterectomy eight years ago and I am just as miserable today as I was when it happened. I feel like a computer that is short circuiting out when I get an intense flash. They trigger anxiety, ruin my sleep and make me miserable all around. My 70+ y/o mother who entered meno naturally said she maybe had a couple hot flashes and that they weren't intense. I am so jealous, haha.
@@StoneyB I’m glad someone mention anxiety with hot flashes! It’s awful because it’s very hard to go to work feeling like that ! I did get the wave 1 about a year ago! Now on hormone therapy but I’ve got to be honest everyone is different so not all works well until you find the right dose or the right kind of hormone therapy ugh …I’m so sorry and I do understand so very well..please find whatever works to keep from not going crazy !
we all feel like we wanna cry! its disruptive on all levels! no one wants to be in a relationship burning up or at work having to take bathroom breaks as a teacher to cool off. or drinking tons of ice water! from periods to menopause us women donot get a break!
I have a Wave 1 and it’s definitely been useful. I am really hoping for a sleeker form factor in the near future; right now, this doesn’t inspire me to upgrade because it’s just not as big a jump for me from Gen 1 to Gen 2 to make the upgrade worth it. Great review, though!
I have the wave 1 ..it works well for menopause or just being hot or cold..I do the 8 hr mode which comes on and off ..the only thing I don’t like is the band that’s a magnet if you get around metal hold on to yourself lol 😂 but I’m just going to change the band and try it out ..this one looks nice and looks like a watch ..for 299 it is expensive but it was worth the buy! I’m might buy this one as well
I hope you do!
well considering all the herbal supplements i've been taking to combat these hot flashes & nights sweats it would have equaled to one of these watches! lol im definetely getting one in a few weeks. i'm sick of being an easy-bake oven!
I have an Embr Wave 2 and I am totally in love with mine. I suffer from horrible hot flashes and I live in Minnesota which is really cold. I sometimes sweat while wearing my heavy duty winter coat can you imagine. It's horrible. But now I have a defense: Embr Wave 🎉🎉🎉🎉🎉
That's so great to hear! Glad you are getting some relief. 😊
It's a shame these aren't available at discounted rates to anyone who's had hormone related cancer or surgery causing medical menopause, the symptoms of which can be up to 10 times worse than natural menopause! I'd love to get one to try, but way out of my price range sadly. I'm 4 years post breast cancer, left mastectomy and chemo, hot flushes drive me crazy, and I can't take HRT. I'm boiling up just writing this! 🥵
My wife is dealing with this now, gonna order her one for a valentines day gift
Me too! Same situation. It’s bad. Completely second everything you said!
Not that good
They now have a $20/month program.
I'm in the same boat as you, but I'm now 7 years out. I purchased this with high hopes, it's been 5 days wearing it and honestly, it doesn't do anything for me. I still get my hot flashes and have to turn on my portable fan. It feels nice to have it on your wrist and I've heard it works for some people, but it hasn't worked for me.
No way. I had severe symptoms of menopause and prempro was fantastic I felt good as new
They had me on the strongest mg. prempro there is and it didn't work some ladies are different glad it works for you though some ladies can buy stuff off the shelf and it works me not so lucky
I purchased this item through Amazon in case I needed to return it. So far, I have worn it 5 days and it hasn't done anything for my hot flashes. It feels good on the wrist when the cold waves are coming in, but it doesn't stop the hot flashes and so far, I still get them every 45 minutes. I haven't seen any difference with this, I guess it works for some people and not others. If you buy, make sure you can return in case it doesn't work for you either.
Thanks for your comments here. To be clear, it doesn’t work to prevent hot flashes; it helps you cope with them.
I'm a guy going through radiation for throat cancer and my hot and cold flashes come on pretty intense. Part of this is also from painkillers. I'm constantly taking on and off various layers of clothing. Do you think this would work for me? thanks!❤
Sorry to hear about your diagnosis. I do think it might help. I find it very effective.
If it was any good the world would know about it.
Chemo threw me right into menopause and my hot flashes are crazy
I'm sorry to hear that, I hope this could help.
Great review! Thanks.
You're welcome, thanks for watching!
Great review… I’m sold!!
Hope you enjoy it!
As a guy with hot spells due to stress especially at night this device helps a lot. It definitely has a psychological/comforting aspect which is why I would only recommend this device for someone with those types of issues. If you just want a personal heater/cooler you will be disappointed imo
😂
Great feedback Rem. Thanks for posting.
Thanks Erin, I'm seriously considering this as I constantly feel warm even with A/C. I tend to feel 15 degrees warmer than anyone else in the room and don't need a jacket when it's 45 degrees outside and everyone else is bundled up! Do you think this could make a serious difference for me?
I found it helpful. It’s hard to say if you’d benefit from this device or a portable fan…?
my ac could be on full blast along w a fan and i'll still be hot! lol im certainly getting this in a few weeks!
@ honesty2476 And did it make a difference for you?
I wonder if this could work on people like me who live with Hyperhidrosis
Exactly why I’m researching it!!!
Thank you so much for this!
You're so welcome!
Who thinks this would make a noticeable impact on a gal who is always cold?
God, i so need one of these. I am currently taking a hot flash pill. It works, but obviously wears off over the day. I need something continuous. I am in the process of finding one so I can have it. Never heard of this device until now, which is good they have something like this cause I need it.
Glad this video helped alert you to a possible solution.
What medication are taking for hot flashes.??
H’mm, 😏. I recently bought this item and was very hopeful as I have Hyperhidrosis and suffer frequent hot flushes even though I went through my menopause eighteen years ago. It has recently got worse so I thought I would try this item. The cost was £299.00 but sometimes desperation dictates spending. It does blast your wrist with an immediate cold sensation and says that it pulses a continued cold sensation through your wrist. I can’t say that I agree with this. After the initial blast of cold, I feel nothing and continue to hot flush. Disappointing. I will persevere with it though and just hope, I guess?
I can guarantee you that you only used the 10 minutes hot flash mode turn on the all night hot flash and use it day and night let it chase the hot flashes it will but you have to give it time to work it won't stop the hot flashes it will make them less harsh and stop night sweats and mind disturbances everyone that get no relief from the embrwave 2 is not using it correctly and is expecting not to get hot flashing anymore it help relieve the hot flash quicker and diminish the intensity faster keep at it.
I like the square one
I do to
I would love to try that device im in my 60ty and i still have very bad HOT 🥵 flashes
I hope it helps!
I really wanted to buy this a couple years ago for my MS, but it’s so expensive! I really wish it was covered under health insurance. 😭
I totally agree!
I totally agree with you this should be covered by your insurance I mean women who don't have the means to buy this get hot flashes too So we have to suffer because we're can't afford it. Doesn't seem right to me. I think that if the people who sell this device make it so you can get it through your insurance they would have a lot more sales ( lot's more ) and less Moody females walking around. Think about it for the masses of women who desperately need help with menopause and this device
@@debrawilkins That’s just NOT how the healthcare world works… You should know this… I’m sure this company would LOVE to have insurance pay for this device. But that’s just not up to the manufacturer. It’s ALL ON THE INSURANCE COMPANIES to make that happen, as it is with ALL MEDICAL DEVICES.
If it was to be considered a medical assistance device they would gouge the price up and u would probably still have a huge out of pocket expense. I seen an ad that you can get it for 20 a month
How does this work during workouts? Is there a rubber style band?
It was fine for me; the size is more an impediment than the band, which is metal mesh.
My question is does insurances cover it? Like I can't pay for that price. But I'm early menopause at 38 cause I had a hysterectomy and the hot flashes are killing me. That would help alot but I don't have that kind of money. If my insurance will pay for it sign me up.
I agree, it is pricey and if insurance covered it it would be helpful to so many.
FSA funds will cover it
Thank you for this video
I just use a water spray bottle, some times i buy the sprays from the drugstore with thermal water
11:42 I would love to have one of those but they have expensive on a fixed income . Wish they would have payment plans
They have a subscription plan, you pay $20 a month to use a refurbished device, essentially your renting the device for 20 a month, no contracts, cancel and return anytime. But it's not a rent to own situation
They do, 20$/month
I have fibromyalgia and I have a hard time controlling my body temp....I wonder if this would work?
I have fibro and other things, I love it. The first few days I wasn’t sure, but the more I use it, the more it’s worth it. I really do sleep better
Your thumb is free.!! The solution is the acupressure point in your wrist. This point is found on the inside of the pinkie-finger side of the wrist, about one-half of the width of the thumb back from the wrist crease. Don’t waste your money or time on this device
This is about $640 in Canada with the shipping and tax! Too much!!
:(
So it just cools your wrist??? And this cools ur whole body down?? Don't know about that
It actually does!
Does this help with MANO-Pause?
Is it water resistant?
It is water resistant, but not water proof. Do not submerge it in water.
The Embr wave works it don't stop you from getting hot flashes they will still come but boy when they come the Embr wave deals with them for me I use the all night cooling all day and all night when I use to get a hot flash it was not just heat my body up it was like mood changes going from feeling normal to feeling like my body was being taken over slowly by an alien my head felt like mind worms were slowly boring into my brain as I was having a hot flash then the drenching of sweat would start I would wake up with a drenched pillow that I would have to let dry before making my bed but wow since using Embr wave it's like I have a new life no more drenched pillows I have been waiting to find my pillow drenched but it don't happen any more and those feelings of brain worms don't happen anymore when I get a heat flash I get a very small perspiration on my forehead and it quickly dries up on its own the flash only lasts seconds the Embrwave detects the hot flash and goes after it like a predator and destroys the hot flash I don't care hot much they charge for it it's worth every penny but they were generous enough to only charge 299.00 but I got mind on walmart for 249.00 you can find bargains if you look around I am not being paid for this review I am a captive that was set free of hot flashes by Embrwave I am so grateful to Embrwave.
I've not seen anywhere it saying the watch DETECTS heat flashes?
Are there side effects?
Yeah, the other side gets warm
What about for surgical meno?
Meno is meno, surgical or natural symptoms are the same
@@gadgetessa7830 I say this *most respectfully* but that is not necessarily true. I have had a forced hysterectomy due to several cancer diagnosis. Surgical or "forced" hysterectomy can in a lot of cases cause symptoms to come on at a more rapid speed and intense rate than those who enter it naturally. So, yes you are correct in saying the symptoms are the same but the rate & intensity differs. I can attest to extreme symptoms myself and I have been dealing with them for 8 years now. They have not gotten any better in that time. I am not a candidate for any medication since they are all mostly estrogen based and the type of cancer I had has a high rate of reoccurrence with estrogen receptors meaning estrogen could cause a cancer reoccurrence for me.
Now you can just use the device for $20 a month !
I have one that I dind't know what it was for😂😂
I liked the wave 1 retro design, wave 2 is too feminine and bubbly
So £300 to put an electric ice cube on my wrist while I sleep?
Your wearing it wrong you supposed to wear it at least an inch from your wrist
You just made me buy one for my mumma! Poor thing has been dealing with hot/cold flashes 😢 giving it as an early christmas/birthday gift since it’s a heafty price! Shes been ogling it for a while though… I feel she’s gonna love it.
Must be fun when trying to type / use a mouse?
Yes… It can definitely get in the way in some situation. Certainly easier to take it on and put it off if you are trying to work on a computer. But definitely a factor for folks to consider.
What's the mechanism inside of it that makes it warm or cool? Is it some kind of vibration?
I don’t know what’s inside but it’s like putting an ice cube there. It can get pretty hot when you set it to that mode. I’ve had mine 24 hours an im happy with it. It may not take them away completely yet but it does make it so they don’t peak. Supposed to work better after a week an your body adjusts. It may not work for everyone but it’s like that with anything we use.
It detect your internal body temperature and regulates it related to hot flashes
It's a peltier device. You can Google them. They're handy little things. It's basically a small electronic heat pump that makes one side cold and the other side hot (it's also what makes portable fridges work). The away facing side must have some kind of heat dissipation for it to work.
I heard operative words in her presentation that caused me to caution
Hot flashes?
Yes
It’s still massive and thick. It’s a waste of money!!!! Very good scam. I gave it a good go and it did nothing but warm or cool on my wrist. Must work like magic/ mental for some people. Plus- wearing a smart watch on one arm and this on another looked ridiculous.
Sorry to hear it didn't work for you. I agree with the watch and this it does look funny.
Biased review. Affiliate links.
I feel like it’s a waste of money. I’d rather just put on a fleece jacket, some hand warmers or grab the electric blanket. Both are much cheaper and will offer much more warmth than this overpriced gimmicky gadget.
For people in need of cooling (not us up in the frigid north) a $20 box fan at Walmart or some reusable ice packs would be a better investment.
I'm interested in this to cope with hot flashes caused by prostate cancer treatment. I need something portable that will help when I'm away from home hiking, shopping, etc, when a fan or ice pack is not feasible. I can't anticipate when they'll hit, so a wrist device would be great. If this actually works, I'd consider it money well spent.
But I agree that for people who just want to adjust to the current weather, it does seem like a waste of money. And I'm skeptical about it's effectiveness.
A box fan is not really the same I can't waitress carrying around a box fan. I do use ice packs but the new restaurant I work at doesn't even have a freezer.
How long does it stay on for until it has to charge again? Could I use it a full day in school?
It says around 9 hours before needing a charge.