You can find several brand versions of this fan on Ebay and Amazon. Sold under the brand names Growneer, Vivosun and Vivohome to name just three, I am sure they all share the same manufacture. Ranging in price from $30 to $55 they claim to a 4 Inch 195 CFM Inline Duct Ventilation Fan Vent Blower for Grow Tent. In all cases, I recommend you buy something else. I cheap price is what attracted me so I overlooked the high number of negative reviews and went ahead and purchased the unit. Unfortunately I waited a month before installing the unit. Turning it on, I quickly found out that you get what you pay for. I was surprised at the amount of noise from this unit and would have returned it if it wasn't past my return time. I ended up mounting it on rubber feet to help reduce the noise. Also notice the packing tape around the unit. This is because it leaks air like a sieve. This unit is not for use outside of your tent. I am also not convinced that this unit comes anywh...