Carbon steel hex washer head Self Drilling Screw , a plastic ring with water-proof and anti-loose function under head , Standard specification .

1. Material : ANSI 1022
2. Case hardness : HV700
3. Core hardness : HV450
4. Size : #8x2 and #6x1
5. Finish : Environmental yellow zinc
6. Drilling speed : 2500P.R.M