PURPOSE: To ensure sufficient holding strength and facilitate the removal of a device by simple structure regardless of the warpage of the device main body and the shock.

CONSTITUTION: A device main body 11 is inserted into a mounting hole 15 from the front plane of a panel 10. Then, when a mounting frame 1 is inserted from the rear of the device main body 11, the latch tooth 6 are permitted to get in over the protruding parts of an engaging groove 14. The mounting frame 1 is pushed until the leading edge of the mounting frame 1 hits the inner plane of the panel 10. When a screw 7 is screwed down into the screw hole 4 on a screw holding part, the head of the screw 7 hits the taper part 5a of a hook piece 5. Force is applied on the top and the bottom hook pieces 5 in a direction that sandwiches the device main body 11 and the latch tooth 6 operate to thrust into the engaging groove 14. Thus, the device main body 11 is fixed to the panel 10 being sandwiched by the front plane flange 13 and the mounting frame 1. The device main body 11 can be removed only by loosening the screw 7.