all light fixtures are rated diffrently the most common ones are 40w 60w 100w 150w in the medium base like an "a-type" light bulb but ive seen em as high as 4000watts @ 10000 volts for mogal (the giant hid base) ya just gotta make sure you base is rated for the wattage/voltage your using ...

on another note im a big fan of 48" 8 bulb bathroom vanity fixtures there like 15-25 bucks depending on quality and finish there rated for 60w bulbs so they have no problem takin the 42watt cfls so thats like 300watts for 30-50 bucks after bulbs and wire
masterjointsmith Reviewed by masterjointsmith on . cfl vs yield When you use cfls do you get very much of a yield or is it pretty crappy.Im upgrading to a 250 watt hps soon but right now i got one plant flowering under cfl's and it doesnt look like there is much there.So if any of you have grown wit cfl's wats the average yield?And what will it be around with my new 250 Watt hps? Rating: 5