Made using 3/4" conduit metal. About $4 for 10ft at your local hardware store. I used M3 screws to fit and tight the parts together. The parts should be able to be scaled so that other size pipes may be used but I have not tested it. Can build it to any size you want, I built mine based off 10 card set up. If you desire you can build it taller so that you can have racks of GPUS above. Enjoy.