ProAm SolidTrax Universal Track Dolly DIY Wheels for Modus System, Set of 4

Build your own track dolly with the SolidTrax quad wheel assembly. It is comprised of 4 polyurethane wheels and 8 precision bearings. The wheels are mounted to a thick aluminum bracket and fitted with dual ball bearing sets for smooth rotation on straight or curved tracks. Fits tracks sized 3/4 to 1-1/2 inch. When mounted to the Modus platform, the track spacing will be 7-1/4 inches (184mm). Steel, aluminum or rigid PVC piping is recommended.