5/16 90° – 1 Flute Hyper Countersink • HSS • For Chamfering, deburring, and countersinking • Can also be used to enlarge holes in sheet metal List Number ZD65020 Fractional 5/16 Decimal Equivalent 0.3125 Overall Length 2" Substrate HSS Angle 90° Package Quantity 1 Shank 1/4 Flute Count 1 SKU: ZD65020 Category: Countersinks Related products 1/4 82° – 1 Flute Solid Carbide Countersink Item #: SC08251 1/4 90° – 1 Flute Solid Carbide Countersink Item #: SC08250 1/2 60° – 1 Flute Solid Carbide Countersink Item #: SC08502