☆★Free Shipping!!★☆ Unopened and Brand New! ☆★ This is a pet door for cats and small dogs. It uses a swing door system, allowing access from either side. Magnets are used to automatically close the door after the pet passes through. You can also lock the door when you don't want them to go in or out. Originally designed for screen doors. It's designed for indoor/outdoor screen doors and windows. It cannot be installed on very thick wooden doors or iron/aluminum doors. An instruction manual is included, so installation is easy if it's a screen door. However, with a little DIY, it can be used on most doors, so I usually install it on the fusuma (sliding paper doors) of rooms where I use air conditioning or heating. This helps save on heating and cooling costs. After using the toilet, they sneak back into the room with the comfortable temperature. ----------------------- 【Manufacturer】: Nicheez 【Entrance Size】: 20.5 x 26 cm (※See image) 【Outer Frame Size】: 24 x 29 cm 【Material】: ABS 【Included】: Mounting screws, instruction manual (very simple, almost a leaflet) 【Applicable】: Cats, small dogs, or other small pets 【Note】: The product I purchased had some burrs on the main body. Since pets will be pushing against it with their bodies, please carefully remove the burrs with sandpaper or similar to prevent injury. 【Shipping Method】: Nekopos (Japanese postal service)