It belongs to the gas discharge lamp light with a higher efficiency about 90 lumens/watt; by changing the metal halide composition to issue different colors of light which also means  regulate color temperature from 4000K ~ 10000K regulation. It is recommended to use 5000K which similar to noon sunshine; with about 3000 hours life. The disadvantage is that gas discharge need high voltage to trigger and ballast to stable current which will increase costs.