Series 37 - Long Series Dimensions to DIN 844. Centre cutting. Threaded shank to DIN 1835D. Shank cutting diameter to +0.04 -0.0. Available in HSS-Co 8% Uncoated (for general production machining), HSS-Co 8% TiCN Coated (extends cutter life and improves work material surface finish) and HSS-Co 8% TiALN Coated (dissipates and resists heat, reduces surface friction coupled with high surface hardness).