KOHLER K-557-K-NA DTV Prompt Digital Three-Port Thermostatic Valve Up to 13 gpm (gallons per minute) maximum flow rate with maximum flow of 8.0 gpm from one outlet 1/2-inch hot/cold supply inlets, three independently controllable 1/2-inch outlets Mounts within standard 2- by 4-inch walls Pre-wired with three-prong plug for connection to 110v AC receptacle Requires K-558 DTV Prompt digital interface and K-559 DTV Prompt mounting bracket (both sold separately)