here is the simplest and save cost smart set of the auto electrostatic install for robot coating, with only the gun and the electrostatic unit. all the function using the originaly control if you already apply with auto coating. First, install the nozzle then connect cable one by one like this is H.V cable, remove and put the H.V cable in, and other side of the H.V cable connent to the power pack, then the other side of the power pack like this cable is connent to the HDA-203 electrostatic controller.