We bought this for fun but don’t really use it. Bought new for $100 and only been used a few times. This thing can really launch lol! You can use it inside or outside because it’s battery operated. We used the balls it came with and other tennis balls fit perfectly! Batteries included. I think this is a fun way to play with your dog, our dogs liked it! Our Joyhound Electronic Ball Launcher Dog Toy signals game-on for interactive fun for you and your dog. This toy allows you to play fetch with the push of a button and choose from three different settings. You can even teach your dog to load the launcher to play at their own pace (remember to never leave your dog unattended). Whether in a wide-open park or your own backyard, it's time to put your game face on. Only at PetSmart. Features: Ball Launcher Launches ball 10-40 feet Fits most standard 2.5-inch tennis balls Includes: 1 Ball Launcher Toy, balls NOT included Intended For: Small dogs, Medium Dogs, Large Dogs, Puppies, All Breeds Activity: Fetch, Interactive Playtime with Humans, Healthy Development Color: White, Blue Dimensions: Tennis Balls: 2.5 inches each Gift Prompt: Great Gift Idea: For hours and hours of healthy fun, look no further for the perfect gift to give or get for your pet. Activity toys are designed for productive play for small, medium, and large dogs. Pet Benefits: Tugging play helps develop healthy impulse control, and strengthens the bond between pet parents and their dogs.