Genuine OEM Hyundai Diesel Fuel Cap, part number 310103A901. This cap is designed to securely seal the fuel tank filler neck, preventing fuel evaporation, spillage, and the entry of contaminants. It also plays a critical role in maintaining the correct pressure within the fuel system for optimal performance and emissions control. Clearly marked 'DIESEL', this cap is specifically for diesel-powered vehicles and includes an integrated tether. Choosing a genuine OEM fuel cap ensures a precise fit and seal, preventing costly fuel loss and maintaining the integrity of the vehicle's fuel system.