Threaded Rods, Bolts, Nuts manufacturer / supplier in China, offering Carbon Steel Zinc Plated Eye Bolt, DIN580, 65mn Spring Lock Washer, DIN7980, Hex Tap Bolt, Asme B18.2.1 and so on.
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Drilling speed testing of our self-drilling screw, with 8mm thick metal for #12 drilling screw, 5mm thick metal for #10 drilling screw.
The drill point for #12 screw is #4, and #3 drill point for #10 screw.