1/4" Mechanical Zinc Finish Medium Split Lock Washer / HOLE DIAMETER: 0.255 INCHES MINIMUM AND 0.260 INCHES MAXIMUM OUTSIDE DIAMETER: 0.487 INCHES MAXIMUM MATERIAL THICKNESS: 0.062 INCHES MINIMUM AND 0.072 INCHES MAXIMUM END ITEM IDENTIFICATION: MEDIUM MINE PROTECTED VEHICLE - AMPV; MRAP - COUGAR AMBULANCE; MRAP - M-ATV UI; MULTIPLE LAUNCH ROCKET SYSTEM (MLRS); ARMORED MULTI-PURPOSE VEHICLE (AMPV); MRAP BUFFALO MK2A2; A4 BRADLEY FIGHTING VEHICLE; A3 BRADLEY FIGHTING VEHICLE; HIGH-MOBILITY ARTILLERY ROCKET SYSTEM (HIMARS) HARDNESS RATING: 45.0 ROCKWELL C MINIMUM AND 53.0 ROCKWELL C MAXIMUM CRITICALITY CODE JUSTIFICATION: FEAT SPECIAL FEATURES: WEAPON SYSTEM ESSENTIAL MATERIAL: STEEL COMP 1060 OVERALL OR STEEL COMP 1561 OR STEEL COMP 1064 OR STEEL COMP 1065 OR STEEL COMP 1566 OR STEEL COMP 1069 OR STEEL COMP 1070 OR STEEL COMP 1572 OR STEEL COMP 1074 OR STEEL COMP 1075 OR STEEL COMP 1080 MATERIAL DOCUMENT AND CLASSIFICATION: 66 FED STD ALL MATERIAL RESPONSES OVERALL PROPRIETARY CHARACTERISTICS: NPAC SURFACE TREATMENT: CADMIUM OVERALL OR ZINC SURFACE TREATMENT DOCUMENT AND CLASSIFICATION: QQ-P-416, TY2, CL 2 FED SPEC SINGLE TREATMENT RESPONSE OVERALL OR MIL-C-81562, TY 2 MIL SPEC SINGLE TREATMENT RESPONSE STYLE DESIGNATOR: 108 SPLIT HELICAL-RIGHT HAND