China Screw suppliers Details锛?/span Name:Hexagon head self drilling screw Standard:DIN7504K Size:ST2.9-ST6.3 Material:Carbon steel / Stainless steel Coating:Zp, Yzp, HDG, Geomet, Black, Self-color Delivery time:Usually about 45days Certification:EN10204: 3.1 Report Introduction锛?/span DIN7504K hexagon head self drilling screw, are threaded fasteners that drill their hole and thread it as they are installed. Usually only recommended for use with metal, self-drilling screws are available with wings that enable use when fastening wood to metal. The drill point length should be long enough to penetrate both materials being attached before the threading portion reaches the fabric. DIN7504K hexagon head self drilling screw head has six flat sides that a wrench can grip to turn from the side, enabling use when there is no space above the head for a screwdriver. The serrated flange acts like a washer to increase the fastener's bearing surface and distribute the clamping force over a larger area, providing a grip that resists loosening. ROCK CATALOGUE Drawing锛?/span China Screw suppliers website:http://www.rock-hardware.com/screw/