Self-tapping pan head combination screw designed for rapid fastening in metal, plastic, and composite materials. The 4.0x9mm specification delivers optimal holding power for light to medium-duty applications. Features a pan head profile for flush surface mounting and a combination drive system accommodating both Phillips and slotted drivers. Hardened steel construction ensures durability and corrosion resistance. Ideal for electrical enclosures, panel assembly, and general fabrication work. Sold in bulk quantities for wholesale efficiency.