Hex Socket Countersunk Flat Head Screws Bolts M5 M6 M8 Black Grade 10.9. Size : M5 M6 M8. Pitch：0.8mm（M5）/1mm（M6）/1.25mm（M8）. Material: High Tensile Grade 10.9 Steel. The product is made of 10.9 grade high strength carbon steel, which has the characteristics of high toughness, good cold and hot working performance and excellent machinability.
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