NTI Boilers Firetube Boiler 95% AFUE 10:1 Turndown, 110k-Input, 101k-Gross Output, 107 lbs, Water Content-1.4 gallons, 1-1/4" MPT Heating Connections, 3/4" MPT Gas Connection, 2" or 3" Vent Size, Dimensions-17"D x19-3/4"W x38-1/4"H