Black F436 Flat Washer Size: #6-3", M3-M72 Grade: ASTM F436 Head mark:JM,F436 Material: C1045+Heat Treatment Products information: Flat ... /SAE, DIN125A, DIN125B, DIN126, DIN433, DIN440, DIN7349, DIN988, DIN9021Size: #6 – 3”, M3-M72Material: Carbon Steel, Alloy Steel, Stainless Steel, Brass,copper ...