Read more Durable Aluminum Frame With reinforcement material, aluminum material,compare with plastic, it is more strong and long life. Weather Resistant With two flaps,more energy efficient than single flap pet doors,soft vinyl flaps with magnets that hold the flap closed,held up just fine with heavy rains and windy areas. Slide-in closing panel Ownpets large door come with metal back plate, and 2 pins that lock it in place on top on the inside, you can close the door at night to protect your safety. Dust Strip The Dog door frame with dust strip,it can keep dust and bugs out of the house. Read more Give your furry friend freedom The dog door fits in different material doors and walls , heavy-duty aluminum frame and high quality vinyl flap,it is anti-bite and chew for large dogs. Tight seal and magnetic closure keeps wind and insect away from house inside. Give your furry friend freedom to go in or out without asking for your help to open the door. Package: 1 * Pet Door 1 * Pack of Screws & Nails 1 * Cutting Template 1 * User Manual for Installation Read more How to measure dog size? 1.Make sure the width of your pet's chest 2.Measure the dog hight from the back to shoulder bottom Our Large Pet Door Flap opening is 11.6 ''W* 16.8''H. Read more