Play in a tunnel is an instinct for a cat, Our folding collapsible cat playing tent is designed to connect this tunnel with a tent or many tent , it can grow up by connecting two tent with one tunnels, you can build up a castle for your kitty if you needed. Tips: 1. Put a sand bag inside or connect to the side of tunnel to prevent the cat rolling around. 2.Connect with cat tent with zipper door,take care about the zipper head, make sure it is correctly connect before you zipped. Package Included: X1 CAT TUNNEL X2 SAND BAGS