#410 Stainless steel unslotted indented hex washer head, self Drilling, passivated & waxed screw. This self-tapping screw is recommended for light-gauge sheet metal applications (see drill capacity guidelines below). Self-drilling screw drills a hole and taps a thread in a single operation. The drilling point must fully penetrate all pieces of material being fastened before the first thread engages.  The washer and hex head are formed together as one piece. The underside of the hex washer head provides a flat bearing surface that reduces the likelihood of crushing mating surfaces when you drive this screw.  Application: Attaches metal to metal. Drill Capacity (in.): .035 - .176 Installation: A 5/16” hex nut setter or 5/16” drive socket with torque limiting nose piece set at a maximum of 2500 RPM drive speed recommended. Do not over torque as it can cause the head to snap or stripping of the threads. Installed fasteners must penetrate a minimum of three full threads beyond the metal structure. Specifications: • Manufactured to SAE1 J78 for dimensional specifications • Meets F.I.P.2-1000.7 for torsional strength and drill speed • Medium degree of corrosion resistance