Baohui hardware electronic co. ltd supplies various of screw, which follow the standard of GB/DIN/ANSI& BS/BSW. Otherwise, we also can made the Non-standard bolt, do it follow sample or drawing or with Requirement Details of you. Commonly , we supply the screw/bolt follow the GB standard. The range is from M1. 2 to M8. From the shapes of screw head, there are Binding/Pan/Flat/Oval/Truss/Round and Hexagon, we usually call those for short by : B-head/P-head/F-head/O-head/T-head/R-head and H-head. From screw drive type, there are Slotted(flat or straight), Phillips(Crosshead), Pozidriv(Supadriv), Robertson(square), Hex, Hex socket(Allen), Six-bloe, Spandrel etc. Particular detail could be consultations. Welcome to visit our manufactory, or contact us by Email and skype. We will reply all of your consultation as soon as possible.