The cap is available in two sizes.

S/M: The small/medium size (available in navy and dune) fits head circumferences from 53–56 cm. The cap has adjustable velcro, meaning it can be suitable for children and teenagers, as well as adults.

M/L: The medium/large size (available in black and dune) fits head circumferences from 57-59 cm. The cap has adjustable velcro, making it suitable for adults. 

How to measure
When measuring, use a flexible measuring tape.
Measure around the whole head, just above the ears, across your forehead and to the back, in a straight line.