According to embodiments of the present invention, a clip includes: a plate spring member having a leg portion and flange portions; a pin member having a shaft portion and a head portion. The leg portion has: inclined portions outwardly extending from a bent portion; engagement portions inwardly extending from the inclined portions; and abutting portions connected between the inclined portions and the flange portions. The shaft portion has: a proximal-side diameter-expanded portion; and a distal-side diameter-reduced portion. When the plate spring member is assembled with the pin member and flange portions abut a front side circumference of the mounting hole, the diameter-expanded portion abut the abutting portions to expand the leg portion through a further pushing operation of the pin member thereby engaging the engagement portions with a back side circumference of the mounting hole.