Sturdy metal frame. The connections are also made of metal. Why connect the connections to the frame with PLASTIC connectors?!?! After about a year of use, the plastic connector broke off (see photo) and I've taken good care of the stand. I don't see a way to fix this so it ends up in the trash which is so disappointing! It was good while it lasted but I expect it to last a lot longer given the price. December 2018 Update: I appreciate BackPainHelp supporting their product and sending me a replacement, so I've changed my rating from 1 star to 3 depending on how well the new product holds up. I'll try to remember to update my review in about a year. Hope this one lasts much longer. If not, I hope they strengthen the connections to eliminate the weak link in an otherwise great product. Update March 2019: I am increasing my rating to 5 stars. The new stand is much stronger than the previous one. In addition, the connectors remain blocked, the previous ones were disconnected, which was annoying and caused the stand to break. Excellent work! I would recommend it to anyone who wants a solid stand that doesn't change settings often (takes a few minutes to install).