4-Pin Molex to 3-Pin Fan Adapter
With this cable you can connect a fan or pump with a 4pin Molex connector to a 3pin connector (i.e. fan controller or motherboard).
For example, do you have a noisy 4-pin Molex case fan directly connected to a power supply?
Then with this adapter cable, you can connect the fan to a fan controller or your motherboard and regulate the speed.