To prevent the worsening of assembling ability and demounting ability and to prevent the deformation of a resin claw due to heat.

A resin claw 12 is molded integrally with a side defroster 10 and a reinforcing rib 32 is formed at the back 12C of the resin claw 12. A reinforcing rib 32 is inclined in the direction of the width of the resin claw 12, one end part 32A reaches a root part 12A and the other end part 32B reaches the back side of an engaging part 12B. Thus, at the side end part 12D of the resin claw 12, since height H1 from the root part 12A of the reinforcing rib 32 is low, rigidity is low and the resin claw 12 is apt to deform toward the back part 12C side. Since, at the side end part 12E of the resin claw 12, height H2 from the root part 12A of the reinforcing rib 32 is high, rigidity is high and the resin claw 12 is hard to deform toward the back part 12C side.