NTI Boilers Watertube Boiler 93.5% AFUE 8:1 Turndown, 200k-Input, 181k-Gross Output, 125 lbs, Water Content-1.2 gallons, 1" FPT Heating Connections, 1/2" NPT Gas Connection, 3" Vent Size, Dimensions-18-5/8"D x17-1/2"W x29-7/8"H