Metal fully sprung equalized trucks mount with a #2 or 2-56 screw, sold separately. The Barber S-2 70-ton roller bearing truck is a logical development from the original friction bearing truck first introduced in the 1940s. This model is based on a prototype built in 1967, however, the basic design was first introduced in the late 1950s. The sturdiness of the Barber(R) S-2 truck is evidenced by the forty plus years it has rode the rails to date. A careful observer will spot these trucks in interchange use today. This truck can be used under almost any pre-1970 built 70-ton rolling stock. Truck Features: * Self Centering Action - Trucks self align themselves parallel with the car for easier placement on track * Code 110 (.110) 33 smooth back wheels * Accurate markings * Incredible detail true to prototype * Non-magnetic metal wheels * Highly flexible sprung trucks * Metal side frames and fully sprung bolster * Smooth tracking free rolling contoured insulated axles * RP-25 free rolling wheels