Maui Toys Liquid Core Wave Hoop 34" The patented liquid core makes hooping 10 times easier than a regular hoop. Wave Hoops make hooping cool with their holographic colors and its liquid core, there is nothing like it on the planet. The size of the hoop is 34.5-inch, and comes in a variety of bright and holographic colors. The Wave Hoop is a fun take on a classic toy. Kids will like the bright colors and that it's easier for them to get and keep the hoop going thanks to the added water inside.The Wave Hoop is for ages 6 and up. The Wave Hoop is for ages 6 and up. Wave Hoop has been the number one selling hoop this decade. It has been in the top 10 summer toys the past 10 years, today's kids know "Wave Hoop" before "Hula Hoop"