Features: It can effectively prevent reverses flows, ensures that the water flows always maintains one directions, and provide stable and good performances. Make of Rubber and P0m materials, it is resistant to wear and corrosion, and can work in a highly pressure environment. Small in size and easy to installation, it is suitable for plugging into the hose or hard pipe of the corresponding diameter to prevent backflow or siphoning. The plastic check Valves is suitable for inlines spring check fittings, plug check valves, and so on. Suitable for various liquid fluid controls systems, including household water use, agricultural irrigation, industrial process controls. Specifications: Materials: Rubber and P0m Mouth diameter: (1/2'') / (3/4'') Size: As shown in the picture Package Includes: 10pcs Plastic Check Valves note: Please allow 1-2cm errors due to manual measurement, make sure that you do not mind before you order. Due to the difference between different monitors, the picture may not reflect the actual color of the item.