Thermal Expansion Tank;Type Inline;Inlet/Outlet Connection 3/4 Inch Male Threaded;Tank Material Steel;Tank Inner Lining Polypropylene;Temperature Rating 200 Deg F;Pressure Rating 250 PSIG;Tank Dimensions 12 Inch Diameter x 14 Inch Height;Tank Capacity 6.4 Gallon;Tank Warranty 1 Year;Diaphragm Type Heavy Duty Butyl;Air Charge Type Factory Pre Charged;Air Charge Capacity 55 PSIG;Options Sight Glass;Inclusions/Features 3/16 Inch Shrader Valve with EPDM Seat, Stainless Steel System Connection;Application Commercial Closed, Potable Hot Water System;Applicable Standard ASME, NSF/ANSI 61, ISO 9001:2008;Lead-Free;Finish Red Oxide Primer;Maximum Acceptance Volume 3.2 Gallon