Kids Swim Vest Size: M / Suggested for weight: 15-19kg/33-41lbs; Recommend age: 2-3 years L / Suggested for weight: 19-30kg/42-66lbs; Recommend age: 3-5 years XL / Suggested for weight: 30-35kg/66-77lbs; Recommend age: 5-8 years The function *Assists kids learning to swim, give enough buoyancy, let the little one trying swimming away from parents' hands. *Offers complete freedom of movement in the water, encouraging kids to develop a natural swimming position. *Maintain the child's temperature in the water, to prevent cold *Gave parents all peace of mind when their kids fall in and kids will quickly grow in confidence in the water. Note: This product should be used under full supervision of a parent or adult.