I've had this wrench forever but have never figured out the open end. It has a couple of notches in there for something. The box end is normal and it's a Craftsman. Thought maybe someone has run across one or knows what it is

For taking nuts and bolts off or on without taking wrench off after broken loose.Kind of like a ratchet effect
Some people love them and some hate them.Never thought I needed them



 

I have some that Snap-on made. Yeah, Don't use them much.

Thanks for enlightening me, not sure it will be coming out of the toolbox anymore than it has up till now.

i think they were called charlie wrench or speed wrench

Craftsman called theirs "Quick Wrench". I suckered and bought a set years ago and should have spent my money on something else. Kind of a novelty like the wrench that fits everything.

For a time my daughter was on the look out for a tool that dad did not have. The Craftsmen Quick wrenches have been part that. As well as Craftsmen end wrench with splines rather than a hex or 12 point head. As there are in a holder they got tossed into one of the pickups, so not used often but do work well. The quick wrenches have been helpful on occasion.

The biggest disappointment was a Vice Grip with a triangle head for somewhat striped hex heads. Just too much of a club to fit when needed it the most. The biggest success was a Vice Grip in the normal large size but has an opening to grip 2 inch pipe or a bit more.