Hayward H-Series Above Ground Pool heater is a lightweight but heavy duty heater. Built with the durable cupro nickel heat exchanger which offers exceptional protection against premature corrosion. Will keep energy cost down by reducing pump run time to heat your pool. Low-nox emissions meet air quality standards in all low-nox areas. Intended for altitudes up to 2,000 feet.BTU: 135,000Thermal Efficiency: 82%Heat Exchanger: Cupro NickelHot Surface Ignition: Silicon NitrideCombustion: Fan assistedLow NOx Emissions: YesDigital Thermostat: YesRemote Compatible: 2-wire and 3-wire120V Power Cord: YesWater Connections: 1-1/2 in FlexGas Connection at Heater: 3/4 inInstallation Location: Outdoor OnlyDimensions: 21-1/2 in W x 29-3/4 in D x 22-1/2 in HFootprint Dimensions: 16-3/8 in W x 27-5/8 in DHeater Weight (lbs): 100