This aluminum cat door mounts directly into a window track between 27 and 32 inches wide, using a 5-inch adjustable length to lock in a snug fit without any drilling. A 4-way locking system lets you switch between in-only, out-only, two-way access, or full lock, so you can control exactly when your cat can come and go. The magnetic flap pairs with a brush-lined edge for a quiet, self-closing seal that helps keep drafts and bugs out while your cat moves freely through the 7.6 x 10.3 inch flap opening. Setup is tool-free: just place the unit in the window track and tighten the side knobs. At 7.5 pounds, the sturdy aluminum alloy and glass frame resists scratches from daily use, and measuring your window track before ordering ensures the adjustable range fits your exact window.