Cool Runners Pro Series Secure Aluminum Portable Pet Expandable Exercise Enclosure 6 Sections (25"H x 36"L Per Section) Quality Lightweight Aluminum Pet Pen Prevents Rust and Cleans Easily Great for Indoor or Outdoor Use Collapses Quickly for Easy Movement and Storage Includes Velcro Straps to Secure the Pens During Storage and Transport Expandable Design Allows for Easy Expansion. Multiple Pens Can Easily be Interconnected