Take your dog’s playtime to new heights with a perfectly weighted ball that flies higher and bounces further than ever before. With their near identical weight, Zeus NITRO Balls deliver all the fun and excitement of tennis balls, with an added bite-resistant layer that’s perfectly gentle on your dog’s teeth. With natural rubber core for an increased throwing distance Chew-resistant yet gentle on teeth Durable and forever bouncy Comes in 3 different sizes to match your dog’s build Available Sizes: Small - 5 cm diam. (2 in) Medium - 6.3 cm diam. (2.5 in) Large - 7.6 cm diam. (3 in)