1. The controller only controls the speed of the four standard specification PWM fan, do not turn off the fan. With full digital control, temperature setting and precise control. It integrates manual speed regulation and automatic temperature control and speed regulation function. Manual speed control from 10%-100%, each 5% is a gear. Automatic temperature control speed from 30 degrees Celsius, there are 49 kinds of temperature zone combination. 2. Input : red black power is only welding 12V and negative power cord, as a general use. The is equipped with a 2510-3P plug, which is used to measure the speed of some main board wire fan ports. 4P interface facilitates power acquisition from chassis. 3. Temperature probe: small black 's head is short, low heat capacity. It is suitable for testing narrow space and air temperature, and the response is relatively fast. The ring probe is enclosed inside a ring metal head with a diameter of 4.2mm. It is suitable for mounting on the radiator or other heating object surface with screws. 4. Manual automatic integration control: Manual control without temperature probe. Click / double-click button up / down gear. Each shift continues after 20 seconds, and the gear is automatically stored. The No. 2 indicator flashes in 20 seconds (when the temperature control is invalid). When the flash is stopped, it indicates the file has been stored. The 3 /1 indicator light is always on when you can not continue to increase / not continue to reduce the position. 5. When the temperature probe is installed, the manual speed is used as the initial low speed (bottom speed). When the temperature exceeds the accelerating temperature, the fan speed accelerates smoothly with the increase of temperature. When the temperature reaches and s the sum of the acceleration temperature and the acceleration width (full speed temperature), the fan runs at full speed. color: Material:PC+Metal Package Contents: 1 x DC 12V 4 Wire Temperature Control Speed Controller Governor Regulator Only the above package content, other are not included. Note: Light and different displays may cause the color of the item in the a little different from the real thing. The measurement allowed error is +/- 1-3cm.