MS9561E, MILITARY STANDARD: BOLT, MACHINE-DOUBLE HEXAGON, EXTENDED WASHER HEAD, CORROSION AND HEAT RESISTANT STEEL, .500-20 UNJF-3A (02 SEP 1993).
MS9561E, MILITARY STANDARD: BOLT, MACHINE-DOUBLE HEXAGON, EXTENDED WASHER HEAD, CORROSION AND HEAT RESISTANT STEEL, .500-20 UNJF-3A (02 SEP 1993).