PWM splitter cable: the wires are 26 cm, sleeved in black braiding with a 4 pin female connector at one end and splits to 2 male connectors at the other end 1 to 2 Converter splitter: PWM fan splitter is convenient to use,solve main board 4 pin interface not enough,extend 3pin to 4 pin interface. Function: This fan Y splitter cable supports 2 fans connecting with a single motherboard fan header, increase airflow in your computer case, reduce the accumulation of heat within the chassis. Motherboard PWM fan 4-pin Female to 4-Pin Fan Male + 4-Pin Fan Male(3 needle, in order to avoid the signal speed at the same time the conflict, Slave 4-pin fan misses one needle, does NOT have temperature control function(PWM)),compatible with 3 pin Case Fan and 4 pin PWM Case Fan. Package includes: 2 pack computer fan splitter cables in total, please ensure your motherboard fan header is capable of the additional electrical load before purchasing