Package Includes: There are 4 pieces 2 types of male/female air quick connectors, 2 ordinary SH20 and 2 ordinary PH20. High Quality Material: These air quick connectors are made of high quality iron. Nickel plated surface for rust, corrosion resistance and good sealing. Easy to Install: You just need to push back the snap ring and insert the hose connector plug. Make sure to put the snap ring back into the position lock to quickly connect or disconnect the tool and air line. Wide Application: These air quick connectors are widely used in the connection between pneumatic devices and air hose.