616 Series, 40 Gallon, Natural Gas Water Heater, 40,000 BTU's, 1" Insulation, First Hour Rating 70, 41 GPH At 90 Degrees Rise, For Installations Altitude Rated To 10,100 R Value 8.00, EF Rating .59, Draft Diverter Outlet Size 3" With Integrated Adapter For 4" Vent Option, Factory Installed T & P Valve, Next Generation FVIR Approved, Stainless Steel Flame Arrestor, Air Intake Entire Base Of The Water Heater, Door Mounted Manual Reset TCO, Not For Use In Mobile/Manufactured Homes, Unit Dimensions: 61-3/4"H x 18"D, 6 Year Tank & Parts Warranty. Self Powered Honeywell Millivolt Gererator Gas Control Value on Units after 4-1-2011