Starrett Countersink Gages are offered in three different angles so that the gage sets on the angular side of the countersink, as opposed to a chamfer gage which sets on the top edge of the chamfer. FEATURES Ground surfaces are of hardened tool steel Indicators AGD design 100 Deg Angle Directly reads the large diameter of the countersink Includes set master ring Includes set master ring SPECIFICATIONS Made in America: Yes Type: Countersink Gage Range (mm): 4 - 9mm Graduations (mm): 0.05mm Dial Reading: For 100 Degree Countersinks