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Exercise Pens make a good indoor/outdoor playground for pets. Each pen includes 8, 2' wide panels that can be set up as a 16' "fence" or exercise pen. Made of durable, solid steel construction with a rust-resistant, electro-coat finish. The drop-pin design ensures there are no exposed screws, wires, or pins. This pen features a 3-point locking door and provides easy access to your pet while keeping them contained. It easily folds flat and features a convenient handle for storage or travel. Recessed fasteners protect your floor's surface making is great for indoor use.