To realize a firmly fitted condition of a male device attached to one of two members into a female device fitted in a mounting hole provided in the other of two members to improve a connection condition of two members to be connected through them.

The female device 2 is provided with a hooking protruding part 23d on an outer face, has an elastic piece 23 having an inner face facing a fitting space 21, and is constituted such that the hooking protruding part 23d is hooked in a hole fringe ha due to springing after the elastic piece 23 is once bent inward by a mounting hole H1 in accordance with fitting into the mounting hole H1. A lock protruding part 24 hooked elastically in a locked protruding part 14 formed in the male device 1 in accordance with fitting of the male device 1 is provided in the fitting space 21. A pressing protruding part 15 pressing and coming into contact with an inner face 23c of the elastic piece 23 of the female device 2 to press the elastic piece 23 outward in accordance with fitting into the fitting space 21 is provided in the male device 1.