3.0l Water Reservoir Bubbler Tank 3.0L Water Reservoir Bubbler Tank 3 NPT 1/4" x 3/8" Tube ID 3.2 Quart Tank measures 6.33" x 7.75" x 4.25" Tank Comes with (2) 3/8" Barbed Elbows and (1) 3/8" Barbed Direct Connection 1/4" return and inlet fittings are placed at bottom of tank for less moisture problems on the HHO gas outlet hose