Authentic McCormick 6521878M2 transmission gear, also identified as a 2nd speed gear. This genuine OEM component is engineered for precise fit and reliable performance in McCormick CX series tractors, including models CX100, CX105, CX110, CX110L, CX50, CX60, CX70, CX75, CX80, CX85, CX90, and CX95. It serves as a direct replacement for original parts, crucial for maintaining optimal transmission function and efficiency. Also compatible with certain Case IH CX series models.