Self-Tapping Screw - Type A - Slotted Indented Hex Head - Zinc Plated Steel - 5/16"-9 Thread - 1-1/2" Long

Self-tapping screws create their own threads but require a pilot hole. The hex head has an external hex head that protrudes above the surface. The externally driven head allows greater torque to be applied to the screw compared to other screws that are internally driven. The slotted drive has a straight-line notch grooved into the surface the head and is designed to be used with flat-headed screwdrivers. Zinc plated steel offers good corrosion resistance in applications not exposed to excessive moisture.