This high-quality training kennel is perfect for puppies and small dogs. It’s loaded with safety features to keep your pet safe and secure in his/her "own" special space. It includes a locking system on the door, top, base and casters. Double tops open outward for easy pet access. The plastic base detaches easily for cleaning; and casters provide easy movement from room to room. Assembly required. Recommended for small dogs 8 to 18 lbs. (4-8kg) 1 ¼" space between slats Door is 13 ¼" wide x 15 1/8" high Top opens to 22 3/8" x 13 ¼" space Slots in base hold PAW TRAX Doggy Pads securely in place