iv never seen them in 5" just 4 and 6"

i have a 6" with a 600w hps bulb in it, it keeps it so cool i can touch the bulb after it ru nning for 12 hours

are yo uinthe market for a bake a round pyrex tube to make your own?
mellogold Reviewed by mellogold on . 5/6 inch Cool Tube & 4 inch Fan/Filter Hi there, I've set up a budbox and the temps are getting a bit too high so I think the best way to go would be to get a cool tube. Recently I bought a 4 inch fan/filter but now that I'm in the market for a cool tube, they all seem to be 5 or 6 inches! Would it be ok to just use my 4 inch fan with this cool tube, I could duct-tape my existing ducting on there somehow: http://www.basementlighting.com/Merchant2/merchant.mv?page=1/PROD/RE6 I know there are guides and I could make my own but I'm Rating: 5