Pitch: 0.4mm（M2）/0.45(M2.5) / 0.5mm（M3）/ 0.7mm（M4）/0.8mm（M5）. Coarse Thread Hex Socket Head Cap Screws Allen Key Bolts steel 12.9 Full Thread. Head Style: Socket Cap Head. The product is made of 12.9 grade high-strength Carbon steel material, which has the characteristics of high toughness, good cold and hot processing performance, and excellent machinability.
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