Size: 7Nominal Diameter Small End: .3297"Nominal Diameter Large End: .4220"Nominal Overall Length: 6-5/16"Nominal Flute Length: 4-7/16"Has A Square Shank For Use By Hand In Tap And Reamer WrenchesDesigned To Ream And Deburr Holes By Hand Into Which Standard Taper Pins Will Fit