To consider environment by facilitating separation of an insert member and resin material with different materials in separation of the insert member and a plastic molding member.

Smaller diameter part of the insert member also having a larger diameter part is pressed into a boss part of the resin material. A cutout is formed at the head part of the boss part of the resin material. Accordingly, by applying an impact load or prying with a minus driver, the insert member is easily removed from the resin material.