The chin strap is used to stabilize the M-1 helmet system under dynamic conditions. The chin strap consists of 16mm (0.6 in.) cotton webbing open chin cup that is sewn on one end to 25mm (1 in.) nylon webbing. The other end has a snap fastener socket which attaches to a stud on the end of a second 25mm (1 in.) nylon webbing. The free ends of the nylon webbing are threaded through adjustable buckle clips. The chin strap is attached to the helmet by force fitting the adjustable buckle clips over the D-Rings located on each side of the steel shell. Materials Used are Cotton and nylon webbing; steel buckle clip. Weight: 38 gm (1.3 oz.)