M8 DIN 7980 High Collar Lock Washer Mechanical Zinc Finish / HOLE DIAMETER: 8.1 MILLIMETERS MINIMUM AND 8.5 MILLIMETERS MAXIMUM OUTSIDE DIAMETER: 12.7 MILLIMETERS NOMINAL MATERIAL THICKNESS: 4.0 MILLIMETERS MINIMUM AND 4.7 MILLIMETERS MAXIMUM END ITEM IDENTIFICATION: 2335-01-567-4930 HARDNESS RATING: 44.0 ROCKWELL C MINIMUM AND 51.0 ROCKWELL C MAXIMUM MATERIAL: STEEL OVERALL SURFACE TREATMENT: ZINC OVERALL SURFACE TREATMENT DOCUMENT AND CLASSIFICATION: ASTMB695 ASSN STD SINGLE TREATMENT RESPONSE OVERALL STYLE DESIGNATOR: 108 SPLIT HELICAL-RIGHT HAND