Offering a silent way to reduce the airflow of a fan, the Ruck Transformer Based Speed Controller - 3.5A is a robust and reliable addition to any grow room.
Manually adjustable through five different voltage levels corresponding to fan speeds, the advantage of the voltage stepper over variable resistors is the lack of hum created by the resistance.
As well as being unwanted noise, this hum is also a sign that the capacitors in the fan are being put under strain and their lifespan is being reduced. This is especially true when a variable resistor is used with the larger inline fans.
 x Ruck Transformer Based Speed Controller - 3.5A | 5 Step | for ISO-Max & Max Fan