Detailed Product Description Features: 1)Designed to prevent refrigerant from being polluted in refrigerant and heating circulatory system 2) Can effectively keep pollutants which gather in the same direction from reversing 3)Successfully saves two check valves and two regular dryers, reducing complex tubes and relative fees 4)Internal check valves allow flow and filtration action in either direction 5)Capable of dissolving pollutants such as moisture and acid 6)Unrestricted installation location 7)Two kinds of connection methods: ODF, SAE 8)Corrosion resistant paining 9)Safe operating pressure: 4.14MPa