This is a jig used to remove keytops and/or keyfronts with a router. The keystick is clamped in place, and the router uses a template guide so that you don't route the plexiglass guide on the sides. You adjust the router plunger to reach the keytop surface, and then ADD to that depth however much keytop and wood material you wish to remove. Follow the guide - about 3 passes, side, side, middle, and you're done with the top. The other jig with the screw and locking wing nut is to measure the distance from the top of the guide plate to the uncut original keytop. Then that measurement is transferred to the keyfront, if you want to mill it off as well, to the same depth.#GenesisJig