NTI Boilers Watertube Boiler 95.5% AFUE 11:1 Turndown, 110k-Input, 98k-Gross Output, 91 lbs, Water Content-1.2 gallons, 1" SWT Heating Connections,3/4" SWT Domestic, 3/4" MPT Gas Connection, 2" or 3" Vent Size, Dimensions-15-5/16"D x15-3/4"W x29-5/16"H