Very thick plastic. Good sized to cover a full size couch. This worked very well to cover furniture that has been infested with bedbugs for removal and to prevent spreading. It fit with plenty of extra room over a full size couch. It's best to slide it over the top, tip the couch onto it's back, making sure to keep the plastic under it as you do, and then tape it up on the bottom. Be sure to remove any wooden legs or to pad them so they don't tear the plastic.