Suitable SizeSize Small - ( Age of 3-7 months old, weight 11-24 lbs); Size Large - (Age of 7-24 months old, weight 13-38 lbs).S (inner diameter 15CM), L (inner diameter 16CM recommended size), XL (inner diameter 19CM)Complete ProtectionPrevent flipping from sides, Prevent flipping backwards, Raised front and widen , Shoulder strap, One click unlock to take off the float. Breaststroke and backstroke, an ideal swimming posture for Our baby. Easy to learn kick and swim in a horizontal position.Baby-safety MaterialPVC material with thickness of 0.35mm. All of our baby swiming float are assed the Gas detection, all parts have passed the ASTM, CPC and CE Standards.TIPSPay attention that DO NOT be full up inflating the inflating float, 80%-90% of inflating is enough.