Our cat loved her catio and watching the birds and outdoor activities from her safe perches in this large catio. The design is flexible so it can be attached to a pet door in a window or door, attached to an open door. Includes a top for complete safety. I have all the parts and fittings, all thats needed are zip ties to connect to your preferred assembly. Panels are 3' x 6', with 2 panels long by 1` panel wide, making a 3'w x 6'l x 6'h structure.