Folding design, easy to storage and use, portable, detachable and washable, easy to clean. Mesh window is designed around, breathable and visible, 2 zippered doors, one on the top and one on the side. It can be used indoors and outdoors, providing enough space for your pets to exercise and play, keep your pet safe and secure with the Portable Pet Play PenSentence 4. Eight nylon and mesh sides provide just the right amount of light, shade and ventilation.Sentence 5. Mesh door zips up and ties back with hook and loop self closures, removable nylon and mesh zippered top provide easy access to pet.