7/16"-#21 HSS Threaded Shank Stop Countersink BoltsandNuts.com The tip of the hook

The tip of the hook comes to a sharp 30-degree tapered point to keep the strength as close to the tip as possible

Part Number: BIT-D/APY

Part Number D/ACTS

Part Number: M10C70HCSB/FT

Drill Size: U

7/16"-#21 HSS Threaded Shank Stop Countersink BoltsandNuts.com The tip of the hookProduct Description Countersink cutters may be used in all popular adjustable or micro stop countersinking units utilizing a 1 4 28 threaded shank drive. Made from the finest high speed tool steel. Precision ground to exacting tolerances and form relived to insure concentricity of 100 degree countersink angle. Brand Drill America Part Number TSC7 16 21 Size 7 16" #21 Material High Speed Steel Finish Uncoated (Bright) Body Diameter 7 16" Shank Type