Abstract: A cylinder lock plug that utilizes an axially moving sidebar. The sidebar is displaced axially by a key positioning mechanism on the blade of a uniquely configured key. Also on the key are unique short grooves on the lateral sides of the key blade running substantially perpendicular to the longitudinal axis of the key blade. The short grooves are configured complementary to an inner surface of the axially moving sidebar. Only the properly configured key can receive the sidebar as the key is turned to rotate the cylinder lock plug and the short grooves receive the inner surface. The invention is meant to be used with additional locking mechanisms, such as, for example, tumblers.