Item Type: Check Valve Shell: PVDF (Polyvinylidene Fluoride) Tightness: For VITON Fluorine Rubber Diaphragm 1/8 Inch: Usually Suitable for Soft Hoses with an Inner Diameter of Approx. 3-3.5 mm / 0.12-0.13in 3/16 Inch: Usually Suitable for Soft Hose with Inner Diameter of Approx.4-5 mm / 0.15-0.2in 1/4 Inch: Usually Suitable for Soft Rubber Tubes with an Inner Diameter of Approx. 6-7 mm / 0.2-0.3in Package List 1 x Check Valve 1The one-way check valve is made of PVDF (polyvinylidene fluoride) material, which is strong, wear-resistant and durable 2The check valve nozzle is designed with a pagoda-shaped slot, which is non-slip, non-toxic, airtight, and has good adsorption performance 3The one-way check valve is easy to install, convenient for you to unscrew and replace 4Normal performance at 2560, strong resistance to acid, alkali and salt corrosion 5Widely used in auto parts, machinery industry, household appliances, agriculture, etc.Check valve is suitable for fluid system to prevent backflow of liquid, or for pneumatic system to prevent backflow of compressed air