To easily unlocking a panel lock in closed state wherein a cylinder lock is removed.

An operation body 91 projecting rightward on a back position of an attachment hole 59 in the bent part of a working body 43 is formed in one unit. The operation body 91 is pushed up and operated to lift the operation body 91 with a general tool K such as a driver inserted from the attachment hole 59 in a state wherein the cylinder lock is removed so that the working body 43 in lowering state by energization of a coil spring is moved upwards against the coil spring. By rotating a hooking body, a hook-like member at the tip is removed from the hooking body to unlock, and the hooking body is made unhooked state to open the front panel.