S.Drilling Screw - Truss-Head (3/4-inch)

Cavalry self-drilling screws, three quarters of an inch long, with a truss head. The broad low head spreads its clamping force over a wide area so it holds thin sheet and soft board without pulling through, and the extra quarter inch over the half-inch version lets it pass through two thicknesses of framing or a sheet plus a spacer before reaching steel. That suits steel stud framing where sections overlap, boxed and doubled studs, fixing sheet through a layer of board, ducting seams with a gasket, and trims and flashings with packing behind them. The point drills its own hole as it drives, so nothing is pre-drilled. Stop as soon as the head seats flush - running on strips the thread it has just cut.