To allow easy adjusting of floating amount, for easy realizing.

A connector 2 is placed on a panel 1. A fitting hole 2a of which a diameter D2 is larger than a diameter D3 of a female screw part 1a is provided to a position corresponding to the female screw part 1a of the panel 1 of the connector 2. A U-shape block 4 is so placed on the panel 1 as to stride over the connector 2, not to contact the connector 2. An insert hole 4a is provided to the position corresponding to the female screw part 1a to the U-shape block 4. A male screw part 5a of a fitting screw 5 is inserted into the insert hole 4a and the fitting hole 2a, and is screwed into the female screw part 1a while a head part 5b is abutted with the U-shape block 4.