Kadee metal products have been my de facto standard for their excellent quality and performance. Their #523 metal wheels perfectly fit in my pre-1960 rolling stock fleet and are as smooth operating as can be asked for. With a touch of weathering, the wheels with their ribbed backs can really stand out if you look. The metal axles on these wheelsets are near indestructible and produce a well balanced and smooth operating freight car or caboose truck.