AT Combined Drill & Countersinks

Alfa Tools produces combined drill and countersink bits—specialized 2-in-1 cutting tools that drill pilot holes and form countersunk recesses in a single operation. Engineered with precision-ground 82° countersink angles to match ASA (American Standard Association) rivet and screw standards, these combination bits ensure flawless flush-mount fastener installation for aerospace, sheet metal fabrication, and high-precision assembly. Available in HSS, Cobalt, HSS Long Length, and Solid Carbide options, our range covers all standard ASA sizes from #000 to #8 and beyond.