These are powered rotate mechanisms - put wheels on them, and they're also called turtles. We use crane bearings as the basis for these machines, for maximum rigidity and capacity. They are very stout, and will provide a stable platform for any rotating scenery. They come with many different mounting options and configurations to suit the application. Enquire with your specifications for an adjusted price.
Features 
          Crane bearing pivot
          Rugged construction
          Motor reducer drive assembly, with encoder
          Variable speed, reversible pilot operated controls, with all necessary cabling and connectors
          Complete CAD drawings