Wera is even selling self adjusting wrenches, which tighten themselves when you turn them. The big drawback is that the adjustment range is quite small. All ad

Wera is even selling self adjusting wrenches, which tighten themselves when you turn them. The big drawback is that the adjustment range is quite small. All adjustable wrenches have the inevitable problem that they are easier to break then their solid counterparts and have some flex in their construction.