Material: Plastic 90 Reeds. The size 2.9cm*1.1cm. It's standard size for most store bought balls/ toys. Good value. Much cheaper than replacing the toys. Fun little things These are a life saver if you have a kid in squeaky shoes and live near sand/dirt. These are fun and make buying squeaky toys for your dog a lot easier. Now just about any toy can be a squeaky toy. These are great and you use your recycle bottles to fit in the dogs toy. You drill a hole in the cap, put it in and it work.