Feature Versatile Freezing Capabilities - The Cold Shot Freeze Kit can freeze all types of liquids in steel, copper, cast iron, aluminum, and plastic pipes ranging from 1/8" to 2" (10 mm - 60 mm) using carbon dioxide (CO2). Time and cost-effective - This CST2 pipe freeze kit is faster and less expensive than traditional "refrigerator-type" units or "bag-type" units, faster and uses less CO2 than "bag-type" units. Allows for quick and efficient repairs without the need to drain water lines or systems. .