The Evolution Zinc Coated Tek Hex Head Gash Point Screw for Light Steel, with a 19mm Bonded EPDM Washer, is designed for fixing profile metal sheets to timber purlins. Made from carbon steel and AISI C1022 material grade, with a Zinc coating. Twin thread form, a drilling capacity of 0.5-1.2mm and a recommended drill speed of 1500-2500 RPM.