This gauge has been designed by Clarks to help you measure your child?s feet with confidence, in the comfort of your own home. It is recommended for children with a Clarks infant shoe size 10, approximately the age of three, up to adult size 10. For younger children or those with feet smaller than infant size 10 our Toddler gauge is recommended. Each gauge comes with step-by-step instructions and an on-line video demonstration is also available . Further help and support is on hand in store, if required.