The 4RS-1 is a universal 4-outlet power expansion module. It can be used with any of TrolMaster’s “plug-in” style device modules to expand the number of devices that can be controlled by the Hydro-x. A single 120-240 volt “trigger” cable on the 4RS-1 connects to your device / control module. When the device module is activated by the Hydro-x, the 4RS-1 trigger cable will turn on each of the 4 receptacles on the 4RS-1 with a 3 second time delay between each outlet being activated. That minimizes high start-up (inrush current) and allows up to 4 devices to be safely controlled. The 4RS-1 must be installed with a 120/240 volt power circuit (up to 50-amps @ 240vac). Three wire terminals inside the unit accept up to #6 AWG wire making connections to the power source easy. * This plug is NOT U.L. or E.T.L listed.