Self tapping screw material: Stainless Steel,Carbon Steel, Brass, Bronze, Aluminum & Aluminum Alloy, Titanium and Titanium Alloy, Alloy steel, Iron Self tapping screw head type: Pan head, Truss head, Flat head, Oval head, B head, Round head, Hexagon head, Hexagon washer head, Hexagon socket head, Bugle head Self tapping screw driver / insert / recess: Slotted recess, philips recess, cambo slotted recess, pozi drive recess, square recess, socket recess, torx recess, triangle recess, slotted and aquare recess etc. Self tapping screw surface treatment : Plain, Black/gray phosphated, black(BK), black/yellow/white/blue zinc(RoHS), black/white nickel, rainbow, dacromet, electrophoresis, etc. Self tapping screw thread type: 1. Identify by shape: Half thread, full thread, multi stage thread, 2. Identify by function: machine thread, self tapping thread (coarse), self drilling thread, 3. Special thread: Triangle thread, High-low thread, fast thread (D/W thread), C/B thread, Umbrella thread, etc. Self tapping screw hardness: class 4.8, 8.8, 10.9, 12.9. Self tapping screw size: screw thread diameter from 1.4mm to 12mm, thread length from 1.5mm to 130mm Self tapping screw inspection: Salt atmosphere testing, Hardness tester, Projector, Torsion meter, Vernier calipe