Hayward"s Universal H-Series Heater combines advanced technology with universal fit flexibility, making it the perfect heater for new or existing installations. This new design offers left-side or right-side electric, gas and water connections, with 110v or 220v electric hook up. Universal H-Series Heaters feature an easy to use digital LED control panel along with industry leading hydraulic performance for reduced circulation time. Low NOx emissions meet standards set by the California South Coast Quality Air Management Commission for 2001 and the Texas Natural Resource Conservation Commission Code. Built to last, each heater utilizes Silicon Nitride Hot Surface Igniters and Cupro Nickel Heat Exchangers for superior durability. 84% thermal efficiency. For residential use only. 1 year warranty.