Smooth wheel set is commonly used in diesel era seen most vehicle. The Kadee wheels set according to the most rigorous standards Manufactured in the USA. Performance: RP 25 contour, non-magnetic metal wheels, insulating and axle. Product performance: Standard Index 110 (110). Precise markings. Wonderfully detailed, faithful to the original product. Non-magnetic Metal wheels. Smooth tracking Free rolling, contour the axle. RP – 25 free rolling wheels. The axle. Freight & Passenger Car Use.