Drywall Screws, Recess Bugle Head, Fine Thread, Hard.

Material: Hardened Carbon Steel C1022A

Drive type: Philips,Torx, Hexagon socket, Square

Core hardness: 289-449HV

Surface hardness: 560-653HV

Surface Treatment: Zinc Plated, Yellow Zinc Plated

Standard: DIN, ASTM

Certification: ISO9001, CE

Non-standards: OEM is available if you provide the drawing or sample