Yep. I use a 600watt MH conversion bulb. The only thing im not sure about is that it does not have rand name so im not sure how much light its really putting out.600 mh exists its a conversion bulb. i run the hort eye hps and used to do sunmaster. i have actually found a better mh than sunmaster. it has higher par rating and slightly less lumans. lumans are for humans par is for plants. tried the switch and they love the par light. made by solar max