The valve body is made of brass bar and its exterior can adjust the flow rate of the valve, especially for R-22 air conditioning systems and refrigerating devices of small refrigeration capacity. The inlet connection has removable 100-mesh filter screen (only for SAE conic connection). The materials of the valve is made of bar and stainless steel (ODF connection materials are red copper). The valve can prevent rust and corrosion by the greatest extent. The connector is welded with valve body by high strength silver welding, capable of preventing leakage permanently. The sensing elements are sealed with advanced knife-tightening technology. It is both artistic and free of leakage. The valve needle is precisely aligned with valve port to avoid influencing the operation of the valve due to the large variation of pressure drop, which can offer an accurate control under the working condition of great variation. The sensing elements No. is 43 knife-tight connection, and the length of standard capillary tube is 76cm (30 inches).