Even though the cheap inline fans are rated at those cfm's they will not push as hard through ducts as Centrifugal fans rated at the same cfm's will. Centrifugal fans barely loose any cfm's when venting through ducting while doing it with much less noise. I will never have another friend go"do you hear that howling". The "your just high" remark wasn't cutting it anymore. Peace
BlazeIdo Reviewed by BlazeIdo on . Duct fans I was wondering if anyone has used duct fans to power their exhaust. I am hoping to get one to put inbetween my growspace and my carbon filter. Does anyone have any tips or suggestions? Duct Diameter:.................... 4" Unit Weight:....................... 2.50 Lbs. Max Boosted CFM:............. 80 Free Air CFM:..................... 65 Amps:................................ 0.30 Housing Length:.................. 6" dBA:.................................. Rating: 5