The SWOOSH® Drain Gun® 20G Cartridges are designed to clear drain lines instantly. The larger 20 gram SWOOSH® CO2 cartridges deliver 800 PSI of oil free air to clear the line, with 25% more capacity. SWOOSH®, SGC-12, CO2 Cartridges, Replacement, For Use With: Drain Guns, Aluminum, Red/Silver, Import