The SWOOSH Drain Gun Big Shot is designed to clear drain lines instantly. Larger 20 gram SWOOSH CO2 cartridges deliver 800 PSI of oil free air to clear the line, with 25% more capacity. Each unit comes equipped with a tapered fitting to work on 3/8 in 3/4 in drain openings. Flexible hose assembly maneuvers through cabinets, coils and hard to reach drains. Reduces labor costs and time on service calls.