The slotted drive has a linear slot for use with a flat-blade driver. The flange acts like a washer to increase the fastener's bearing surface and distribute the clamping force over a larger area, reducing damage to the material being fastened. The hex washer head has six flat sides that a wrench can grip to turn from the side, enabling use when there is no space above the head for a screwdriver. The black oxide finish offers mild corrosion resistance and lubricity. Steel is often used in applications where strength is the primary consideration.
The Type AB point has the conical tip of a Type A point with the finer spaced threads of a Type B point. The black oxide finish steel sheet metal screw with hex washer head and slotted drive has a Type AB point for forming threads in thin metals between 0.015' and 0.050' thick and resin impregnated plywood.
