The Yellow Jacket A/C Flush Kit system removes refrigerant oil, moisture and contaminants from system components and lines during retrofitting and compressor replacement. You simply fill the canister with Yellow Jacket flushing agent (which is compatible with ESTER, PAG and mineral oil lubricants), pressurize with shop air and flush each component. The kit includes a rubber-tipped flush gun, a canister with an adapter and an A/C flush catch hose. The company believes their system removes contaminants economically and completely, therefore reducing warranty claims and saving money.