US Patent 7484392 Cylinder lock and key

A cylinder lock provided with a thick key including an elongated base having two surfaces. A serrated wall extends from one surface of the base. A key groove is formed by the serrated wall. A rib is formed on the other surface of the base. The cylinder lock is further provided with a rotatable rotor including a keyway into which the thick key is inserted. A first cavity is formed in the keyway and shaped to enable insertion of the base of the thick key. A second cavity is formed in the keyway and shaped to enable insertion of the serrated wall of the thick key. A third cavity is formed in the keyway and shaped to enable insertion of the rib of the thick key. The keyway enables insertion of a thin key in lieu of the thick key.