This sliding glass pet door suits medium dogs up to 40 pounds and adjusts to fit door heights from 75 7/8 to 80 11/16 inches with a simple turn-knob mechanism, so there's no drilling needed during setup. The flap uses a triple-layer PVC construction, with tough outer layers that resist scratching and daily impact and an insulating middle layer that helps block outdoor heat, cold air, and drafts from coming through. A rotating hinge keeps the flap swinging smoothly through frequent use without wearing out. When you need to keep your dog inside, overnight, while you're away, or during bad weather, a slide-down blocking panel closes the opening in about a second, and a button lock secures it in place. Weighing 16.9 pounds, the door is light enough to install and remove without tools, which makes it a practical choice for rental homes.