Does anybody else have trouble with the types of those that have no flat side on the head?
I starting losing them all the time and realized the heads without a flat side would wiggle themselves loose without using a big flat washer behind them.
I was pulling my hair out (what's left of it) trying to figure why I was losing them all the time. Now, I look for the ones with the flat side to the head and I stopped losing them.
I guess I've never had one that was strong enough to really bite a knuckle...