Introduction: D266 is a high manganese steel surfacing electrode with low hydrogen potassium type coating AC/DC+ . (When AC welding, Open circuit (no load) voltages of arc welding should be higher than 70V). When surfacing use low current, narrow bead, hammer or water quench immediately when hot to reduce crack tendency. Use in austenitic high manganese steel. Due to the appropriate quantity of Molybdenum added to the weld, it increases the wear and crack resistance. Recommendations for welding: High manganese steels, in as cast condition or as weld metal, are sensitive to hot shortness and may crack if subjected to excessive heat. Under normal conditions the base material should not be preheated and interpass temperatures above 200 °C should be avoided. Welding outdoor in very cold weather, the base material should be warmed up to 50-100 °C. Weld metal hardness, (all weld metal): HB ? 170 Machinability: Grinding is normally applied. Overheating must be avoided. Redrying the electrodes: 200 °C, 2 h.