Harvey Tool 875640-C8 | 5/8" Diameter x 5/8" Shank x 3-1/2" OAL 90 Degree Included Angle TiB2 Coated Carbide Picatinny Attachment CutterPicatinny Rail Form Cutters are designed to MIL STD 1913 specifications. Mill the entire Picatinny Rail in a single pass without tool changes, cutting on entirety of the concave form and OD flat at the tool's end. Designed to the MIL STD 1913 specifications Mill the entire Picatinny Rail in a single pass without tool changes Cutting on the entirety of concave form and OD flat at end 4 helical flutes for better cutting action . 005" max radii for all