The McCormick 6664336A1 is a genuine OEM 12V 90 Amp alternator designed to provide reliable electrical power for McCormick X4 and X5 series agricultural tractors, including models X4.30, X4.35, X4.40, X4.45, X4.50, X5.35, X5.45, and X5.55. This alternator is also compatible with various Landini models such as the 4-070, 4-070C, 4-080, 4-090, 4-100, 4-105, 5-085, 5-095, 5-105, and 5-115. This essential component ensures optimal charging of the battery and powers the vehicle's electrical systems, maintaining peak performance and operational efficiency.