The McCormick 6666885A1 Mass Kit is an authentic OEM component designed for various McCormick X-series tractors. This essential kit provides additional mass, crucial for optimizing tractor stability and traction during demanding agricultural operations. It is compatible with a wide range of models including the X4.20, X4.30, X4.40, X4.50, X4.60, X4.70, X4.75, X5.20, X5.30, X5.40, X5.50, X5.60, X5.70, X5.80, 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. Weighing 20 kg, this mass kit ensures proper balance and enhanced performance for your McCormick machinery.