Permanent in-door install: Cuts into the door itself for a clean look and a stable mount Five sizes, two colors: Small, medium, large, XL, and XXL in white or black aluminum 0°F to 115°F flap: Clear vinyl flap with perimeter weatherstripping seals against drafts year-round Fits standard interior and exterior doors: Works on most wood, fiberglass, and steel residential doors Made in USA, locking cover included: Built domestically and backed by a 3-year warranty The Liberty Pet Door for Doors is a permanent in-door pet door for dogs. It installs directly through the door, with frames on both sides and the flap hanging in the cutout. Single-flap configuration only on this model.The aluminum frame and clear vinyl flap are rated from 0°F to 115°F. Perimeter weatherstripping creates the seal. Five sizes (small, medium, large, XL, XXL) cover dogs from terriers up through large breeds. Both white and black are stocked. A locking cover is included for nights, vacations, or trips to the vet.Before ordering, pick size by your largest pet's shoulder width and chest height rather than current weight. Confirm the door has clearance above and below the planned cutout for the frame to seat flat. If you need a flap dimension outside the standard sizes, the custom-dimension version covers a wider range of widths and heights.Made in the USA and backed by a 3-year warranty. Install is a moderate DIY job that requires cutting a rectangular opening through the door.