EasyOut Remote Pet Door Opener Single Latch Product #: EASYOUT-1 Extra remote controls will be available for purchase soon keep one in your purse, another by the bed, by the front door, etc. It presently works with standard wire crates and exercise pens, and is planned for interior doors, chain link kennels, and door flaps. The opener is about the size of a deck of cards, and is easy to install and its 4 AA batteries come pre-installed so it works right out of the box! Great long term value; with a one time affordable purchase you and your pet benefit every day, year after year!