Uniweld 40039 Nitrogen Sludge Sucker and Blaster Kit with Metal Carrying Stand for 20 Cubic Feet Nitrogen Tank The Nitrogen Sludge Sucker and Blaster Kits are specifically designed for multiple uses in the HVAC/R industry (Tank Not Included  Sold Separately) Nitrogen Regulator with protective rubber gauge boots - Maximum Delivery Pressure up to 400 PSI Purging copper lines with low pressure nitrogen displaces the oxygen, preventing oxidation and the resulting scale Pressure testing a system for leaks prior to evacuating and charging will save time and money Cleaning a condensate drain line is easy with a Sludge Sucker or Sludge Blaster