2.00MM HSS-Co 8% 3 Flute Weldon Shank Short Series Slot Drills - Uncoated. Shank Type: Weldon Flat. Centre cutting. Uncoated (for general production machining) TiCN Coated (extends cutter life and improves work material surface finish) TiALN Coated (dissipates and resists heat, reduces surface friction coupled with high surface hardness).