Install a pet door for your dog runs or save yourself the trouble of constantly opening and closing the door for your pet! These doors can be installed with ordinary tools. All that is required is that you cut the opening, and then install the doggie door. These doors are made of polypropylene and polyethylene. Lightweight and easy to install. These doggie doors also include a security door that can be closed as needed. To determine the size for your pet, your doggie door should be 2" wider than the widest part of your pet. For the height, the opening should be 2" taller than the length from the top of the shoulders to the chest, just behind the front legs. Model DG24 Guillotine Style Dog Door Medium Dogs Regular price: $119.00 Sale price: $105.00 Model DG32 Guillotine Style Dog Doors Large Dogs Regular price: $129.00 Sale price: $105.00 Weather Flap for Model DG24 Dog Door $28.00 Weather Flap for Model DG32 Dog Door $28.00 PLEASE NOTE: The following freight surcharges apply for the Ultra, Diamond and Platinum Kennels ONLY!!!! * Add $50 for shipments to states within the Pacific Time Zone. * $300.00 Minimum Order * Add $50 for RESIDENTIAL DELIVERY. * Add $100 for shipments to New York City and Long Island. All of our products are proudly made in the USA. We charge Ohio State sales tax on all Ohio Resident sales unless we have a OHIO SALES TAX EXEMPTION FORM on file. The form is available at the link on the left side of this page. Call Toll Free: 1-800-760-3841 M-F 7:30am-4:30pm EST.