The McCormick 6633678A1 is a genuine OEM filler cap designed for a range of McCormick X-series tractors. This essential component ensures a tight and secure seal for various fluid reservoirs, preventing leaks and contamination. Manufactured to McCormick's stringent quality standards, it guarantees reliable performance and perfect fitment for maintaining your agricultural machinery. Confirmed fitment includes models from the McCormick X4, X5, X6, and X7 series.