beler One Way Inline Check Valves for Fuel Diesel Gas Liquid Water 8 mm -8mm Fulfilled by Amazon-

Specifications Condition: 100% new Color: White Material: Plastic Hose size: 4mm / 6mm / 8mm / 10mm / 12mm Opening pressure: >0.015MPA Compatible: Suitable for water, petrol, diesel, oils and other fluids Item included:1 x one way check valve Please note: Please allow 3-5 mm error due to manual measurement.  Feature: 1) Good quality material, safe and nontoxic. 2) Arrow marked on valve, showing fluid flow direction, Prevents fuel from returning back to the tank and keeps it in the line. 3) Stable characteristics, high reliability. 4) Easy installation and replacement.