This is a genuine OEM McCormick part number 6521915M1, a critical spring component designed for various McCormick agricultural tractors. It ensures proper function and durability in models including the MC series (MC80, MC90, MC95, MC100, MC105, MC115, MC120, MC130, MC135), MTX series (MTX110, MTX120, MTX135, MTX140, MTX150, MTX155, MTX165, MTX175, MTX185, MTX200), T-MAX series (T-MAX 80, T-MAX 90, T-MAX 105, T-MAX 115, T-MAX 120, T-MAX 130), X7 series (X7.440, X7.450, X7.460, X7.650, X7.660, X7.670, X7.680, X7.690, X70.40, X70.50, X70.60, X70.70, X70.80, X70.90), and X8 series (X8.660, X8.670, X8.680, X8.690, X80.60, X80.70, X80.80, X80.90, X80.95). Manufactured to McCormick's stringent standards, this spring provides reliable performance and ensures compatibility with original equipment specifications.