Screw size: M1/M1.2/M1.4/M1.6/M1.7/M2/M2.5/M2.6/M3/M3.5/M4/M5/M6. Head type: It is a pan head (round head) type. The edge of the head is flat and slightly convex. Material: Usually carbon steel is used as the main material, and it is hardened to increase the hardness and strength of the screw.
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