40 gallon, natural gas water heater, 40,000 btu's, 2" insulation, for installations from sea level to 10,100', energy factor .62, recovery at a 90 rise-gallons/ hours38, first hour rating 70, draft diverter outlet size 3" with integrated adapter for 4" vent option, t & p valve, pex polymer lined heat trap nipples, pex dip tube, glass lined tank, mag anode rod, next generation fvir approved, stainless steel flame arrestor, air intake surrounds the entire base of the water heater, door mounted manual reset tco, not for use in mobile/manufactured homes, will void warranty, unit dimensions 62"h x 20"d, 9 year tank & parts warranty, have self powered honeywell millivolt generator gas control valve, meets new naeca 2015 efficiency standards.