Our 100% Merino Wool Long John Bottom is great to wear under sweatpants, pants, or as pajamas. Warm and soft and machine washable. A great layer of protection for playing outside during cold weather. These are children's sizes, similar to American sizes. The size is close to the age. Size 4 should fit a 4-6 year old child. Wool is from Australia, sewn in Denmark.

Size 4 (sometimes marked 110 on the package) is  27 inches, from the top of the waist to the bottom of the cuff.

size 6 (sometimes marked 120) is about 30 inches long, from the top of the waist to the bottom of the cuff. 

Size 8 (sometimes marked 130)  is about 31  inches long, from the top of the waist to the bottom of the cuff. 

Size 10 (sometimes marked 140) is about 33  inches long, from the top of the waist to the bottom of the cuff.