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CDM lamps use one fifth of the power of comparable tungsten incandescent light bulbs for the same light output (80–117 lm/W) and retain color stability better than most other gas discharge lamps. Like other high-intensity discharge lamps, they require correctly rated electrical ballast in order to operate.
This relatively new light source, touted for being compact, efficient, and powerful, is part of the high-intensity discharge (HID) lighting category, which offers the highest efficacy and longest life of any lighting type, and saves up to 90% of lighting energy when they replace incandescent lamps