Features: Specially Designed Safe Space for Puppies - This unique pen box constructed using 3mm tempered glass with MDF board, seamless connection, stronger than the regular glass, shatter-proof, each panel weighs 6lbs, remains robust in place, built with puppy protective ledge around the inside to prevent crushing or suffocating a puppy caught between her mother and the sides of the box, also designed with a more convenient entry door for dogs to go in and go out, no need to detach any panels Carefully-designed Details - This unique pen box constructed using tempered glass with MDF board, which is about 4 times stronger than the regular glass, shatter-proof, built with puppy protective ledge around the inside to prevent crushing or suffocating a puppy caught between her mother and the sides of the box, it is important to have this ledge, especially for larger dog breeds, providing safety and support Indoor Playpen Box - The playpen works great as a whelping box for female dogs to