The ball-shaped version of the Tidal Tank. It provides even more water movement and exercise possibilities. Dimensions: 16" in diameter Material: PVC EAN: 8719327563908 Contains:✔ Tidal Tank Sphere 16" diameter✔ Blue Dye Bottle of 1/3 oz✔ Free Air Pump✔ User Manual✔ Unlimited free access to the video library✔ Unlimited free access to the mobile phone app (iOS and Android) Standard 1-year warranty. The Tidal Tank is comparable with other aqua bags and sandbags. However, since the weight of the Tidal Tank consists of 100% of water, it is constantly moving. This challenges you like no other weight could. As a result, it will allow you to train your balance and functional strength more than any other device.