30 Gallon, Natural Gas, Ultra Low Nox Water Heater, 33,000 BTU, Draft Diverter Outlet Size 3" With Integrated Adapter For 4" Vent Option, .63 Energy Factor, Recovery At A 90 Degrees Rise-Gallons/Hours 36, First Hour Rating 55, 1" Insulation, T&P Valve, Glass Lined Tank, Pex Polymer Lined Heat Trap Nipples, Pex Dip Tube, New Advanced Gas Control System Incorporates An Internal Microprocessor Providing Enhanced Operating Parameters & A Tighter Differential For Precise Sensing & Faster Heating Response To Optimize Performance, Valve Is Self Powered Uses A Thermopile To Generate The Power Needed To Operate Valve & Incorporates Self Diagnostics & Monitoring, 6 Year Tank & Parts Warranty, Unit Dimensions 61-7/5" Tall x 16" Diameter, BAAQMD Regulation 9 Rule 6, YSAQMD Rule 2.37 SMAQMD Rule 414 & SJVAPCD Rule 4902, D Rated Sea Level To 7,700', Meets New NAECA 2015 Efficiency Standards.