1.00Mm Width, 4.0Mm Min Bore, Guhring I.D. Pre-Groove/Chamfering Rh System 104 Insert, 12Mm Reach, Nano-A Coated 1.00Mm Width, 1.00Mm Depth, 12Mm Reach Gv104.0810.045.12.40.R, Nano-A Coated Type Gv104 Guhring Micro-Precision System 104 Carbide Stick Insert With 4Mm Quick Change Shank For Internal Pre-Grooving & 45° Back Chamfering. Guhring Series No. 25142 Order Code 4.009 Made In Germany, Guhring Part #9251420040090 Guhring Inc.