Whatsminer M21s PSU data cable is used to connect the control board and the power supply. Its main function is to supply power to the control board. It is a 14-pin cable. Please note that when using this cable to connect the control board and the PSU, the buckles must correspond to each other, and the plug of the data cable cannot be forcibly inserted into the socket. If it is inserted backwards or wrongly, the control board may be burnt out when the power supply is turned on!