PlexiDor Pet Doors manufacture safe dog doors and cat doors that are ideal pet doors for any animal. Keeping your family and pet safe is our ultimate goal. The plexiglass panels on the Large Silver PlexiDor Pet Door open smoothly with a gentle push and close automatically. The doors are saloon style and no replacement flaps are required. The steel security plate that comes with each door can be attached every night or when you're going away for an extended period of time to ensure no unwanted visitor enter your home.