Screw, Bolts, Nuts manufacturer / supplier in China, offering Directly Factory High Quality M6-M20 DIN912 Carbon Steel Black Cap Socket Bolt, Galvanized 10 Series M4 M5 M6 M8 Rhombus Nut T-Slot Hammer Nut, Tight GOST Duplex Stainless Steel F55 Tc4 Hex Head Cap Bolt for Petrochemical Industry and so on.