Installing a 4 wire harness to operate the lights on a trailer

I install a wiring harness by splicing into the signal light and tail light wires; then I connect the harness to a tent trailer and verify all lights work properly. I use tap-in-splices to cut into the circuits without having to solder ; video below on how to use them :
• How to use a tap-in-sp...

[@DIYVariety]

Right on buddy, job well done