SGC-12 SWOOSH Drain Gun BigShot (20G), The SWOOSH® Drain Gun is designed to blow out drain lines instantly. New 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 3/8in. – 3/4in. drain openings. Flexible hose assembly maneuvers through cabinets, coils and hard to reach drains. Reduces labor costs and time on service calls. Pack of 12 drain guns. This product is made by DiversiTech brand.