Freedom and Comfort - Large cat door lets cats or small dogs enter and exit easily and quietly. Pets do not feel trapped, and you do not need to open or close the door for them. Safer with accessible control - Four lock modes provide flexible access options: Free In, In Only, Out Only, Out, and Full Locked. Use the slide switches to control your pet’s access and help keep stray animals away. Durable construction and efficient sealing - Made of sturdy ABS plastic for long lasting use. Includes a sealing strip and a magnet for alignment to keep out bugs and cat litter odor, while reducing heat loss in winter and air loss in summer. Size and compatibility - Outer size: 19 cm x 20 cm; flap size: 15 cm x 15.5 cm. Suitable for pets with waist circumference shorter than 40 cm. - Compatible with interior and exterior doors made of wood, PVC, metal, or panelled materials. Also suitable for installation in windows, walls, or cat litter boxes. Use scenarios - Home with multiple rooms: install in an interior door to let your cat roam between rooms freely without waking you. - Outdoor access control: place on an exterior door to allow outdoor time while preventing entry by stray animals. - Alternative installations: mount in a wall, window, or near a cat litter box to manage pet access and help control odors.