Using high-quality materials, the quality is guaranteed With switch, can be turned off.The appearance of the product is exquisite Simple and convenient wiring.Stable performance Product parameters:Working voltage: DC12V (can work under 8-15V voltage, please pay attention to the same fan voltage). Fan current: no more than 3A, this current is limited by switches and connectors, and can be expanded by power lines alone. Loss of circuit board itself: less than 20mA without fan. PWM signal mode: 5V25KHZ PWM signal output range: 0%- . Start position PWM adjustment range: 0%-60%. Output interface model: 2510-4P dislocation, conventional CPU, chassis fan socket, pin spacing 2.54mm Function Description: Pay attention to the positive and negative poles and the power supply voltage. After the power supply fan is connected, it can be used. The potentiometer is turned off counterclockwise to , and the clockwise end is the maximum output. A separate small adjustable resistor (starting speed adjustment) on the board is used to adjust the speed of the just-open position If the speed change of the fan is opposite to the adjustment direction, it means that the fan is a reverse-sequence fan, and the (PF) setting point needs to be short-circuited with solder, and the power must be cut off before operation to avoid damage! The short-circuited PWM signal changes in the reverse direction with the adjustment, and the reverse-sequence fan can realize forward adjustment. Precautions: This is a four-wire PWM fan speed controller. It can only control 12V four-wire fans that support PWM speed regulation. For example, many 12V four-wire chassis or CPU fans cannot control 2-3-wire fans. Colour:As Shown Material:plastic+metal Package Contents: 4 x Module Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.