M12 x 37mm OD DIN 9021 Grade C Zinc Finish Steel Fender Washer / CROSS-SECTIONAL SHAPE STYLE: 1 RECTANGULAR HOLE DIAMETER: 13.00 MILLIMETERS MINIMUM AND 13.30 MILLIMETERS MAXIMUM PERIPHERAL SHAPE STYLE: 1 ROUND CENTER HOLE SHAPE STYLE: 1 ROUND THICKNESS: 2.70 MILLIMETERS MINIMUM AND 3.30 MILLIMETERS MAXIMUM OVERALL DIAMETER: 36.38 MILLIMETERS MINIMUM AND 37.00 MILLIMETERS MAXIMUM END ITEM IDENTIFICATION: MRAP BUFFALO MK2A2; MRAP - COUGAR CAT1 A1; MRAP - COUGAR CAT1 A2; MRAP - COUGAR CAT2 A1; MRAP - COUGAR CAT2 A2; MRAP COUGAR EGRESS SPECIAL FEATURES: 12MM ID X 37MM OD DIN 9021 ZINC PLATED FENDER WASHER MATERIAL: STEEL OVERALL PROPRIETARY CHARACTERISTICS: NPAC SURFACE TREATMENT: ZINC OVERALL SURFACE TREATMENT DOCUMENT AND CLASSIFICATION: ASTMB633, SC1 TYPE 3 ASSN STD SINGLE TREATMENT RESPONSE OVERALL