How to fix a spinning shower handle on American Standard barrel-type shower valves (Re-Nu series)

Video about how to fix a shower handle that won't stop spinning on an American Standard barrel-style shower valve. The fix was made by adding a plastic shim washer to the valve stem in addition to the brass washer that comes with the stem assembly. The thickness or number of washers that you may need may vary; in my case I used a washer that was a bit under 1/16 inch thick.
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