The McCormick 3688804M1 is a genuine fuel tank cap designed for various McCormick, Massey Ferguson, and Landini tractor models. This robust cap features a 70mm outer diameter and includes a key for secure fuel tank closure, preventing theft and contamination. It ensures a tight seal, maintaining fuel system integrity across a wide range of agricultural machinery, including McCormick CX, MC, MTX, XTX series, Massey Ferguson 3000, 4000, 6000, 8000 series, and Landini Legend, Powerfarm, Vision series.