Good thread! I was just about to start my own, when I saw this.
My fiendish plan (sorry for the almost-threadjack) is to bolt one of these reels to the side of my shop vac, I'm tired of wrapping the cord around the posts. I was going to ask here if the cord could be reversed on the capstan/wheel inside, so I could retract the male end plug, but thanks to this thread, I've learned about the wiper rings.
Looks like I'll be cutting and splicing at both ends. Shop vac is 5.5g "Shop Vac", 11.5 amp motor, anything too stupid about my fiendish plan?