The Genuine BMW Non-Return Valve (part number 34301162842) is a small, essential component in the fuel system of BMW vehicles. This valve is responsible for allowing fuel to flow in one direction only, preventing the backflow of fuel and maintaining proper pressure within the system. It is a genuine BMW part, meaning it is made to the highest quality standards and is designed specifically for use in BMW vehicles. This non-return valve is crucial for the proper functioning of the fuel system, ensuring efficient and reliable performance.