Abstract: A slide action key shield to hide and protect a key's tumbler cuts and then, on demand, retract to fully expose the tumbler cuts when opening a lock is disclosed. A double capped pin is fixed through the key near the midpoint along the key's length such that each capped end protrudes through a respective longitudinal face slot on the shield to allow the shield to movably cover one half of the shaft of the key or the other. The shield resembles a longitudinally extended sheath open at both ends which conforms to the shape of the key. One end of the shield is flat so that the shield may be easily pushed back by the lock face while the other end is rounded and given side openings to fully retract over the key head without any sharp edges protruding. If the key head is held by a key ring, the retracted shield will be returned by the force of gravity to cover the tumbler cuts when the key is left to hang after use.