3.0Mm Min Bore Guhring Boring/Profiling Lh System 104 Insert, 0.55Mm (T-Max) Offset, 22Mm Reach, Nano-A Coated Left Hand, 0.05Mm Radius, Tialn Coated Gt104.4727.005.22.30.L, Nano-A Coated Type Gt104 Guhring Micro-Precision System 104 Carbide Stick Insert With 4Mm Quick Change Shank For Boring & Profiling. Guhring Series No. 25069 Order Code 4.016 Made In Germany, Guhring Part #9250690040160 Guhring Inc.