The Metro LTTM21C Track Shelving Kit is designed for efficient storage and organization. This Super Erecta® Double Deep Top-Track Mobile Unit Kit features a 21" width and includes essential components such as posts, casters, caster channels, donut bumpers, roller bearing assemblies, and tie-together hardware. Ideal for maximizing space, this kit allows for easy mobility and accessibility of your shelving units. Please note that shelves are sold separately, enabling you to customize your storage solution to fit your specific needs.