Summary

Used for letting a Craftsman saw's (maybe others) on/off switch function. Without a key, the machine won't turn on.

Instructions

My dad broke/lost all of his except one, so this was designed after that one. There are three types.
One with just the legs, which would probably never be able to be removed without some significant work.
Another with a flat top. This one prints out looking nicer, but one side does stick out of the hole it goes into, since it isn't slanted to match the curve of the piece.
The last one has a slanted top, to more closely match the original piece, and it is really only missing the curve on the sides. This one prints pretty well with no support if you have it layed out with the top flat on the print surface and the legs at an angle. If you don't mind a little remnants of the supports on the top, you can print it with the legs straight up.
Edit (2015-12-11): Added files to print the cap and legs separately. They can be glued together afterward, but this seems to increase the strength of the legs.

Craftsman Saw Safety Key