Waistband Instructional Swimming Teaching Train Equipment Swim Safety Belt Float Plate Tool The back belt is adjustable. The kickboards can make your body float easily and increase its buoyancy, which makes beginners to keep balance and learn to swim quickly. Just put the kickboards on buckle the belt to prevent the kickboards from getting falling off. Material:Foam. Size:65cm x 22cm x 2.5cm - 25.59inch x 8.66inch x 0.98inch.