Abstract: A passive belt system includes a continuous-loop belt having a shoulder belt portion fixedly mounted on the upper rear corner of the door and a lap belt portion mounted on the lower rear corner of the door by a storage retractor. The storage retractor normally holds the belt at a fully extended length therefrom but winds the lap belt portion upon disconnect of a release buckle connecting the loop belt with an anchor belt retractably mounted on the inboard side of the vehicle seat. An auxiliary buckle arrangement for converting the system for restraint of a child occupant or child seat includes a pushbutton buckle slidable along the lap belt portion of the continuous-loop belt and a latch plate on the door adjacent the storage retractor which is releasably engageable by the buckle to normally store the buckle.