PLEASE WATCH THIS TIKTOK VIDEO TO EXPLAIN HOW TO MEASURE YOUR HEAD

PLEASE REFER TO THE PRODUCT DESCRIPTION TO FIND OUT WHICH MATERIAL 

To ensure you measure the circumference of your head correctly, the tape measure needs to be over the middle of your forehead, just above your ears and sit on the back of your head. Do not pull the tape too tightly unless you want your hat to be as tight. Measure yourself a couple times just to be sure!
If you do not have a flexible tape measure, a piece of string will do. Once you have measured your circumference and marked the string, lie it flat and measure it! Example: 56cm, 56.5cm etc; Now you have your hat size! A few cm off will not make a huge difference! If you need a smaller size you can always get hat adjusters.