Description:1. Material: Both the screw and the metal washer are made of carbon steel, a zinc-plated surface finish, which is corrosion-resistant; the black washer is made of EPDM, which is wear-resistant and oxidation-resistant.2. Advantages: The hex washer head has a flange with an EPDM rubber washer on the bottom to prevent leaks, loosening and damage to mating surfaces. The underside of the hex head provides a large flat bearing surface that reduces the possibility of crushing mating surfaces. When you tighten the screw, a flexible black EPDM rubber washer bonded to the metal washer creates a tight seal.3. Easy to use: Unlike self-tapping screws, these self-drilling screws drill a hole and tap a thread in one operation. All you need to install them with a power drive tool.4. Application: Hex head self-drilling screws are typically used in metal-to-metal and metal-to-wood applications. Widely used in the electrical and industry, most commonly on thin metals, for example with roofing, steel studs, etc.Specification:Material: Carbon SteelSurface Treatment: Zinc PlatedPerformance Grade: 10.9Thread Dia.: #12 (5.5mm)Length(not include hex head): 2"(50mm)Thread Pitch: 1.8mmHex Head Size: 8x5.4mm / 0.31" x 0.21"(Hex WidthxT)Flange Dia.: 11mm / 0.43"Washer Size: 16 x 3.5mm / 0.63" x 0.14"(D*T)Screw Drilling Range (Plate Thickness): 1.75-5.25mmPackage Content: 50pcs x Hex Head Self-drilling Screws
