M4 DIN 127 Mechanical Zinc Finish Split Lock Washer / HOLE DIAMETER: 0.176 INCHES NOMINAL OUTSIDE DIAMETER: 0.340 INCHES NOMINAL INTERNAL KEY QUANTITY: 12 MATERIAL THICKNESS: 0.023 INCHES NOMINAL END ITEM IDENTIFICATION: F-15SA PART NAME ASSIGNED BY CONTROLLING AGENCY: S/S INTERNAL TOOTH LOCK WASHER MATERIAL: STEEL CORROSION RESISTING OVERALL STYLE DESIGNATOR: 101 FLAT INTERNAL TEETH