iPower Variable Vent Duct Inline Blower Fan Adjuster with Temperature Controller for HVAC Ventilation System, Upgrade Speed Controller1, 750W 6A

The only reason I know this is because I came across a helpful review on here that I now can't find. Inside this unit there is a hole through the circuit board that has a little slotted screw. You turn that one way or another to change the high and low of the adjustment speed. A lot of people will say this doesn't work, and it doesn't make much rpm change out of the box (or if this is adjusted wrong I suspect it will do nothing but on/off). But you can adjust the screw and fine tune it. I came on here to get the fine points from the previous review but couldn't find it. Haven't adjusted the screw yet as I have nothing to test it with at the house. So I can't give more specifics. But I did find the screw.

If you own a iPower inline fan or any inline fan that doesn’t have separate controls then this is a MUST! You can turn it on and off with the controller as opposed to on and off is just plugging in or unplugging. It also has a lowest setting and a full go setting. Just buy it if your inline fan doesn’t have separate controls and for this price, trust me you will be happy you did.

A ++++Very good durable the knob is very crisp and just works very very well out the box.

Does everything it says

The media could not be loaded. The biggest problem is the temperature is so sensitive that the exhaust fan will turn on and off, costing you so much more energy because it won't run for more than a sec then shut off, then back on. The controller needs a delay so it doesn't come on if the temp is jumping by a degree.

The only negative about this device is that there in no signal delay and so the exhaust fan stop and starts constantly. In the long term may damaged the fan motor.

Very good sturdy quality...

the speed controls work great and seem to be good quality. Im sure ill get years of use out of them