1. Optimized for 12V 4-wire fans, this PWM fan speed controller ensures precise control over your CPU or chassis fans. Note that it is incompatible with 2-3 wire fans. 2. For reverse-sequence fans, adjust the (PF) setting by short-circuiting it with solder while the power is off to prevent damage. 3. Installation is straightforward: connect the fan to the power supply ensuring correct polarity, and use the potentiometer for speed adjustments. 4. Designed to handle a fan current up to 3A, this controller is suitable for most standard fans. 5. The controller features a minimal power consumption of less than 20mA without a fan. It outputs a 0-5V 25Khz PWM signal, adjustable from 0% to 100% PWM range and 0% to 60% at start. Working voltage: DC12v (6 to 15V range) Consumption:less than 20mA without fan PWM signal model:0-5V 25Khz PWM signal output range:0% to 100% Start of PWM adjust range:0% to 60% Due to different batches, there may be differences in product appearance and printed text, which will not affect use Specifications:B:3P plug wire Colour:As Shown Material:PC+Metal Package Contents: 2 x Fan speed regulator