The following industry standard sizes for cap hats are available:
•Adult: 56-57 cm (full closure)
•Youth: 54-55 cm (full closure)
•Kids: 51-52 cm (full closure)
•Toddler: 48-49 cm (full closure)
Flex caps size standard
Flex caps measuring hat sizes the way they do for fitted hats. Except rather than having a single size, they have multiple beacause they can stretch.
The size of your cap can be adapted to your own specifications.