CRL's Packaged Rolling Track Assemblies feature a single bottom rail and are pre-packaged in tubes and come in four popular lengths. Assemblies are satin anodized or brushed nickel for a corrosion-free finish. The nylon rollers and plastic guides provide easy rolling and quiet performance. Ideal for small jobs or over-the-counter sales. The kit consists of (quantities shown above): =d603bn">D603 Upper Track, =d652">D652 Guides, =d610bn">D610 Shoes, =d650">D650 Wheels and =d602bn">D602 Lower Track. Note: Maximum suggested panel size is 36 inches wide x 48 inches high (914 x 1219 millimeters).