I have got the Large size for my  7 year old son, 55 lbs, 49 inches tall, average boy. The belt fits him perfectly with good couple of inches of slack. Although everyone everyone comments on the fact that the belt stretches, i wouldn't recommend counting on that as  compensation for the size.  As it stretches it becomes like a rubber band and applies too much pressure. Also, it thins the height of the belt.

I love the fact that it doesn't have any pre-punched holes and it can be buckled  anywhere. The leather belt loop is too tight for my son to use thus the 4 stars. Otherwise I recommend the product.