The package includes: 1 x air compressor check valve, interface diameter: 20/16/10mm. Please check the compatibility and size before purchasing. High quality: The check valve is made of high quality brass, anti-rust, corrosion resistant, high compressive strength, high stability , durable and can be used for a long time. Three threaded connections: The air compressor check valve has three external threaded connections which can be used for pipe connections, tanks gas storage tank and compressor piston pump fittings. Easy to install: The compressor check valve is simple to install and can be easily installed without any tools. Detachable design, easy to clean inside, more convenient to use. Application: Check valve with 90 degree external thread for use in air compressors. It is the best replacement for old or damaged check valves on air compressors.