All our cap sizes share the same construction and overall shape. The circumference (marked as B in the image below) is adjustable by 1 to 1.5 cm. As you move up in size, the maximum circumference increases accordingly.
In addition, the depth of the cap (marked as A in the image) also increases with each size. For example, a size M cap is deeper than a size S and shallower than a size L.
If your head circumference is 58.5 cm, you could fit both an M and an L. However, the size L—with its greater depth—will sit lower on your head and rest closer to your ears.
To decide which size is best for you, think about how other caps usually fit. Do they tend to feel shallow or not deep enough? Or do you prefer caps that sit lower and closer to your ears? Use that experience to guide your choice.
We recommend that you look at our instruction videos on how to measure your head and get a better understanding of the depth of fit. See them down below.