Screwdriver Handle

thingiverse

This screwdriver handle is designed to completely swallow a driver extension; the one I used is a 30mm long cylinder with a 25mm hex shank, and you can see the results in the picture. The extension inside the handle gives it pretty decent strength. As you can see, I use it with another extension so that it has the profile of a full sized screwdriver, but separated the parts fit easily in my pocket.