In a through anchor (10), when an occupant is restrained by webbing (30) in a vehicle emergency, the webbing (30) is moved to the vehicle front side in an insertion hole (22) of a guide piece (18) by movement of the occupant due to inertia, and a vehicle front side end face of the webbing (30) contacts a peripheral face of the insertion hole (22) at high load. A gap is formed between the guide piece (18) and an anchor plate (12). The guide piece (18) is accordingly moved to the vehicle front side with respect to the anchor plate (12) by the webbing (30), thereby enabling occurrence of skewing of the webbing (30) toward the vehicle front side in the insertion hole (20) to be suppressed.