EasyOut Remote Pet Cage Door Opener Single Latch Black Pushing the remote button unlatches the door and allows any size dog or puppy to push it open. Regular manual operation of the latch is not affected, so you can still open/close it by hand whenever desired. Great long term value; with a one time affordable purchase you and your pet benefit every day, year after year! 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! It presently works with standard wire crates and exercise pens, and is planned for interior doors, chain link kennels, and door flaps.