This genuine McCormick 6671637A1 spacer is an original equipment manufacturer (OEM) part designed for various McCormick X-series tractors. It is compatible with models including X4.35, X4.40, X4.45, X4.50, X5.35, X5.40, X5.45, X5.50, X6.420, X6.430, X6.440, X7.440, X7.450, X7.460, X7.650, X7.660, X7.670, X7.680, X8.660, X8.670, and X8.680. This spacer ensures proper component spacing and fitment within the machinery, maintaining optimal performance and integrity.