[MAVRICPOWER] Aluminum Medium Dog Door for Door, Doggie Door with 2 Sliding Lock Panels for Exterme Weahter, Pet Door for Small Dogs Up to 30 lbs

【Flexible Size】The doggie door with expanding tunnel fits paneled, wood, PVC, and metal doors of 1 3/8'' - 2 1/8'' thick. The medium dog door flap opening is 8 7/8”(W) x 12 1/4''(H).. 【Strong & Durable】Dog doors for large dogs are made out of Sturdy Aluminum, for active dogs without worrying about breaking and bitten easily.. 【Good Insulation】Two Magnetic Flaps of dog door designed to enable the door plate to quickly reset after being lifted, as well as keep an even tighter seal when closing.. 【Energy Efficient】Two sliding panels that help maintain indoor temperature and reduce energy costs while providing convenient access for your pet, and keep other unwanted visitors out of the house.. 【Easy to Install】The doggy door that provided with cutting template and step-one-step installation guide,and installation hardware( Self-tapping screw, rivet,etc). Notice: it will be better to use rivet tool for hollow door to further secure.