4.0Mm Min Bore Guhring Boring/Profiling Rh System 104 Insert, 0.60Mm (T-Max) Offset, 27Mm Reach, Nano-A Coated Right Hand, 0.25Mm Radius, Tialn Coated Gt104.4737.025.27.40.R, Nano-A Coated Type Gt104 Guhring Micro-Precision System 104 Carbide Stick Insert With 4Mm Quick Change Shank For Boring & Profiling. Guhring Series No. 25068 Order Code 4.038 Made In Germany, Guhring Part #9250680040380 Guhring Inc.