Designed to help children or adults learn to swim & provide confidence in water * The back belt is adjustable, put the kickboards on your back and buckle the belt to prevent the kickboards from getting falling off. * The kickboards can make your body float easily and increase its buoyancy, which makes beginners to keep balance and learn to swim quickly. * Color: Random; Material: Density foam * Layers: 4 Layers; Small size: Approx. 21.5 x 18 x 8cm/8.46 x 7.08x 3.15inch