Give your pet the freedom to come and go as they please. This Large Deluxe Aluminum Pet Door with adjustable tunnel can be used for large dogs up to 100 lbs. The outer frame measures 19.3 in. x 13.8 in. and flexible flap measures 16.1 in x 11.4 in, with a robust vinyl flap suitable for even the most energetic dogs. This pet door is uniquely designed for doors, screens and walls up to 2.8 in. thick to allow your 4-legged friend the freedom he or she needs for happiness and health. The two way access allows your pet open access with magnetic centering flap to ensure the door shuts after each us. You can also change the access to locked with the locking panel keeping your pet inside or out. Have complete peace of mind knowing that the Deluxe Aluminum Pet Door is designed to last and includes an industry leading 3 year limited warranty. SELECT THE RIGHT SIZE: This Large Deluxe Aluminum Pet Door is suitable for large dogs up to 100 lbs. use the steps below to ensure a perfect fit, 1.Width – Measure the widest part of your pet, usually across the chest. Add an inch 2. Height – Measure your pet from the bottom of the chest or belly to the top of the shoulders, whichever is the tallest part. Add an inch 3. Select Size – Based on your pets width and height choose a door size that fits your pet correctlyImportant: Remember to allow for your pets future growth. Weight rating is to be used as a guide only. Use your pets measurements to select the correct size door.