0.50Mm Width, 2.0Mm Min Bore, Guhring Lh Straight Groove I.D. System 104 Insert, 4Mm Reach, Tin Coated 0.50Mm Width, 0.50Mm Depth, 4Mm Reach Ge104.0050.000.04.20.L, Tin Coated Type Ge104 Guhring Micro-Precision System 104 Carbide Stick Insert With 4Mm Quick Change Shank For Internal Grooving Straight Slots. Guhring Series No. 25125 Order Code 4.006 Made In Germany, Guhring Part #9251250040060 Guhring Inc.