26
Been wanting a prybar to go with my copper EDC stuff for a while but I was worried copper wouldn't be strong enough. Found this old wrench on ebay for $10 and modified it for my needs. Left one of the wrench jaws on there so there's two ways to use it as a prybar. The spike end is rounded enough to probably not tear through a pocket but tapered enough to splice rope or tighten knots. Ended up being 5 1/2" which is a nice size.
This is interesting, what is the rope end used for and why do beryllium copper tools exist?
As Peppycito said, they don't make sparks, which is important if you're working somewhere that could have explosive fumes. The lanyard is traditional for sailors' tools to prevent loss as well as dropping it on someone below. Mostly decorative now but it's convenient to be able to let go of the tool if you need both hands for something.
They don't spark when hit against stuff. Presumably the rope is for not dropping it in the lake.