Size Chart with years and height recommend:<br><br> Size 110 :for height:39 inch-43 inch,recommend 3-4 years.<br> Size 120 :for height:43 inch-47 inch,recommend 5-6 years<br> Size 130 :for height:47 inch-51 inch,recommend 7-8 years<br> Size 140 :for height:51 inch-55 inch,recommend 9-10 years<br> size 150: for height :55 inch-59 inch,recommend 10-13 years<br><br> Note: if your kid is a bit young and not a strong swimmer,please stay with them while swimming.as When the mermaid tail with fin use to swim,it will be a little heavy.Please pay attention on your children