The lower door also features a double lock system, ensuring that cats will not be able to let themselves out of this Richell Pet Pen. If you need to run errands or simply need to keep your feline contained, the Richell Mobile Cat Pen will help you keep the lid on your cat. Richell Mobile Cat Pen: * 1-3/4" space between wire slats * Wire door is 17-3/4"W x 23-3/8"H * Double slide-locking system on door and wire top provides extra pet security * Lockable plastic base protects floor surfaces * 2 elevated platforms allow for nesting/perching enjoyment * Lockable casters provide easy mobility and safety; removable wire top and base * Easy to assemble; instruction manual included