The Cheyenne HAWK thunder is designed to work at its optimal level with the latest version of Cheyenne Power Supplies (either the PU2 or the new PU1).

If you are running the thunder on either the new PU1 or the latest version of the PU2 then you do not need this cable.

An integrated board in the latest versions of the PUI and PUII makes it possible to start the machine with 4-6V.
The thunder has a very powerful motor and as such on some power supplies without this cable a voltage of 10-11 will be needed to start the motor and run the machine, the voltage can then be turned down as required to 3-5 volts without any problems.
This cable eliminates the need to start the thunder on approx.. 10-11 volts and then turn it down, it simply allows the user to start the HAWK thunder at their desired voltage.