3.0Mm Min Bore Guhring Back-Bore/Profile Lh System 104 Insert, 0.70Mm (T-Max) Offset, 17Mm Reach, Uncoated Left Hand, 0.10Mm Radius, Bright Uncoated Gt104.3226.010.17.30.L, Uncoated Type Gt104 Guhring Micro-Precision System 104 Carbide Stick Insert With 4Mm Quick Change Shank For Back Boring & Profiling. Guhring Series No. 25113 Order Code 4.011 Made In Germany, Guhring Part #9251130040110 Guhring Inc.