motherboard 4-pin interface, PWM speed control, can be used for multiple cooling fans, expansion and expansion motherboard 4 pin interface, suitable for CPU or computer chassis fan. fans can be used for 12V DC, or for fixed Molex voltage operation of 5V DC (only 2-pin connector required) cable compatible with standard 3-pin fan power supplies for four 3-pin or 4-pin (PWM connector) PC chassis fans with 4-pin Molex connectors