Cheers, I thought so, I did order a 400w kit, but got sent a 600w?!! I ain't got time to return it n I have a 400w bulb there. With the 600w I have put 2 extractor fans in and put duckting right at light to try dispersed heat + a 4" desk fan inside tent pointing up, but I feel it is still to hot for newly rooted cuttings, I had to take seedling out, where as under 400w they used to grow BIG leaves and be little bushes after 10 days. Would an old 600w bulb give off less heat and be strong enough light to use for a while?