The SMSCOM 4.5amp Twin MK2 Fan Speed Controller allows almost total control of the speed of two fans and helps maintain an optimum temperature in your room or tent. Supplied with a temperature probe, this fan speed controller will allow you to set a desired temperature as well as a minimum speed setting for your fans. With two controls (one for both the intake and extraction) it also maintains negative pressure to help prevent any unwanted smells from escaping. T
hese controllers should not be used alongside fans which have in-built speed controllers.