Step Aluminum Inline Straight Check Valve for Fuel Oil Petrol Diesel Biodiesel Gas Liquid Water Coolant Air Vacuum(8mm) FunctionThis check valve has a built-in one-way function for easy operation and use. Prevents fuel from returning to the tank and keeps it in the line. Clear IndicatorMore fitted on the valve Arrow showing the flow direction of the medium. Convenient to use and adjust during installation or repair. Stable characteristics and a high-reliability check valve for your machine. Stainless Aluminum AlloyMade of high-quality aluminum alloy, this one-way check valve is very durable, rust-proof and for long-term use suitable. The service life of aluminum head for use is longer than plastic heads. Wide Applications Professional check valve - Ideal for marine, automobile, caravan / motor home and agriculture. Also ideal for water pressure pumps and kitchen pumps that are not self-priming. Note: The data are all measured manually. Please allow an error of 1-3cm. Due to the difference between light and display, there is a certain color difference, which depends on the actual object received