Vehicular passive safety device

The invention enables the easy adjustment of the height of the upper end of a shoulder belt (44) of webbing (40) utilizing a shoulder guard (32) provided to a strut (18) provided on both right and left sides of a seat (16). To achieve this, an air belt system (37) is provided with webbing (40) in which a lap belt (43) that cannot be inflated and a shoulder belt (44) that can be inflated are connected, a retractor (38) provided to one side of a seat (16) for winding the end of the lap belt (43), a tongue (41) supported in an intermediate part of the webbing (40) so that the tongue can be slid, a buckle (42) provided on the other side of the seat (16) for connecting the tongue (41) so that the tongue can be detached and an inflator (39) connected to the end of the shoulder belt (44) for supplying high pressure gas to the shoulder belt (44). Right and left shoulder guards (32) are respectively provided to the struts (18) provided on both right and left sides of the seat so that the upper and lower positions can be adjusted, and the upper end of the shoulder belt (44) and the inflator (39) are attached to right or left shoulder guard (32).