The McCormick 6657831A1 is a genuine 12V 40A electrical relay, an essential component for various McCormick X-series tractors. This relay ensures reliable electrical circuit control and proper operation across models including X4.30, X4.40, X4.50, X4.60, X4.70, X4.35, X4.45, X4.55, X5.35, X5.45, X5.55, X6.440, X6.460, X6.470, X6.480, X7.440, X7.450, X7.460, X7.650, X7.660, X7.670, X7.680, X8.660, X8.670, and X8.680. It is also cross-referenced with CNH part number 87302484.