Ultima Selectronic Concealed Toilet Flush Valve, Base Model, Piston-Type, 1.1 gpf/4.2 LpfFor flushometer bowls with 1-1/2″ (38 mm) exposed back spudPOWER KIT MUST BE PURCHASED SEPARATELYFOR INSTALLATIONS WITH REAR ACCESSIncludes 6″ x 6″ (152 x 152 mm) chrome cover plateTouchless operation limits the spread of germsExclusive DynaClean self-cleaning wiper spring technologyIntegral wiper spring cleans refill orifice with every flush to help prevent valve run-onFully mechanical manual override can operate without powerProprietary brass alloy resists dezincification1.1 gpf/4.2 Lpf