Solo Pet Door Automatic Electronic Dog and Cat Door This is best pet door for dogs and cats on the market. It is made in the USA by the original manufacturer for 25 years! Completely automatic. No more opening and closing the door for your pets. A Solo motorized automatic pet door will free you from being a doorman for your pet. Our pet doors are completely safe for your pet because the door closes slowly using only gravity. Securely locked in the closed position for added security. It will also give you the peace of mind that no unwanted intruders can invade your home. Includes a free pet tag sensor. Our pet tags to activate the pet door attach to the pets collar and are magnets and therefore waterproof and do not require any batteries. Comes in 10 different sizes! Works for the smallest pet to the largest dog. When ordering our Solo Pet Door, if you plan to install the pet door in a wall, select the WALL INSTALL item, or if you plan to install the pet door in a house door, select the DOOR INSTALL item.