30cm PWM 3/4 pin Y Splitter Computer PC Fan Power Cable - Black Sleeved BraidedPackage: 1pc Fan Power Cable Black 30cm PWM 4 pin (or 3 pin) Y Splitter Fan Power Cable - Black SleevedYou can use this for 3 or 4 pin fans, it will fit either These 30cm extension cables allow you more choice in where you want to position your PWM or standard 3 pin fans inside your case. The wires are 30cm sleeved in black braiding with a 4 pinfemale connector at 1 end and splits to 2 4 pinmale connectors at the other.Please ensure your motherboard fan header is capable of the additional electrical load before purchasing any of these.Please note - all the connectors are 4 pin connectors, but one of the connectors only has 3 wires. The reason for this is that the sensor wire is not used on this connector as if both fans were sending back information to the mobo it would not be able to understand the information as both lots of information would be coming back through the single connector. What happens is the fan with all 4 wires tells the mobo the information, and then the mobo controls the speed of both fans. These do also have a cut out so you can use 3 pin fans instead of 4 pin if you wish.