The McCormick 6611631A1 is a genuine OEM fuel tank cap specifically designed for a wide range of McCormick X-series agricultural tractors. This essential component ensures a tight and secure seal for the fuel tank, effectively preventing fuel spillage, evaporation, and contamination from debris or moisture. It is compatible with various McCormick X4, X5, X6, X7, and X8 series models, providing reliable performance and maintaining the integrity of the fuel system.