Abstract: A rekeyable cylinder lock includes removeable spacers between top and bottom tumbler pins, and a key bit device for removing a spacer from the pin chamber through the key way. The key bit device includes bitting thereon to position the spacer in the top pin chamber and a cut in the opposite side thereof adapted to capture the spacer from the top pin chamber and remove it from the lock. The spacer is preferably smaller in diameter than the tumbler pins, and the cut is large enough to receive the spacer but too small to receive the tumbler pin. In another embodiment of the invention, a key bit device is provided for placing a spacer into a pin chamber of the lock to rekey the lock. It includes a mechanism, such as a spring, in a cut on the back side of the key bit that is adapted to force a spacer out of the cut and into the pin chamber in the lock.