226 Pcs M4 Bolts and Nuts Set, M4 Nuts and Bolts Set, Black Round Head Hexagon Socket Screws Bolts Nuts and Washers, Hex Socket Button Head Cap Screws Bolts, Machine Screws and Nuts Kit, with Wrench. The hexagon socket round head screw has clear threads, uniform force, and strong force, which can be easily assembled and disassembled with the equipped hexagonal wrench.
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