The Cinevate CIDOAS000004 Ballare Dolly can use a variety of pipe, but we like using schedule 40 white PVC drain pipe, with an internal diameter of 25mm. Any type of pipe (copper, steel, conduit etc) with an internal diameter of 25mm will work with these couplers. The couplers allow you to join the pipe together in a virtually seamless, and very secure manner. The couplers are CNC machined from solid aluminum and have a knurled outer surface for outstanding grip. They expand inside the pipe via access holes that you drill in the pipe. For removal, they can be relaxed, and removed in about 10 seconds.