Features H2Optics Technology for reliable, hands-free operation Manual mechanical override button allows manual flushing if power is temporarily unavailable 3/4 Inch top spud, 13 Inch high and 3/4 Inch copper sweat inlet Factory set at 1.1 gallons (4.2 litres) @ 60 psi (414 kPa) - Not field adjustable Hardwire Flush Valve