Your furry friend will love to play with this toy! The Playball Automatic Ball Launcher allows your dog to fetch the ball, bring it back, and drop it in the hole at the top where it gets ready for auto-launch in a few seconds. This product is specifically made for small dogs. The Playball automatically launches smooth, mini-sized balls which are 1.5 inches in diameter. This machine is NOT SUITABLE for large dogs. This product can be used indoors (a plug is included in the box) or outdoors (there is an option to put in 6 "C" batteries-not included) and will provide yourself and your pet loads of fun! You can easily select between three different launching distances depending on the space you have available, making this an awesome toy for indoor use! Lights on the machine help you easily recognize which distance mode you are in. 3 smooth balls are included in the box. The advantage of these smooth balls, as opposed to the classic tennis ball included in similar products, is that it is saliva resistant and much less likely to get jammed up in the machine.