PetSafe Never Rust Wall Entry Pet Door - Telescoping Frame - Insulates Better Than Metal, Energy Efficient - Interior & Exterior, Weatherproof, Easy to Install & Clean - M

Install Into Your Wall: This pet door is best for homes where it might not be possible to install a pet door into your human door | Durable Frame Won'T Rust: Our pet door is made out of durable plastic that wont rust like other steel options while also providing great insulation | Telescoping Design for Wall Installation: Telescoping tunnel lets you use the door in walls that are 4 3/4 - 7 1/4 in thick; compatible extension kits sold separately for walls thicker than 7 1/4 in | Diy Installation: This do-it-yourself project easily installs in all types of interior and exterior walls; cutting template and step-by-step instructions are included | Energy Efficient: The double-flap provides weatherproofing and energy efficiency, and a slide-in closing panel adds extra insulation when your pet is not using it; PVC frame withstands UV exposure | Medium Size: Medium size for dogs up to 40 lb; flap opening measures 8 1/4 in W X 12 1/4 in H | Gives Your Pet Freedom: Let your cats and dogs come and go on their own schedule perfect for potty breaks or play time | U.S.-Based Customer Care: Our pet product experts are here to help you and your pet and are available by phone, email or chat if you have any questions