Take your actual body measurements as they are more accurate than measuring over your clothes or shoes.
Collar: Measure around the base of the neck where the collar sits.
Chest: Measure the chest at the fullest part, placing the tape close up under the arms.
Waist: Measure the natural waistline.
Inside Leg: Measure from the crotch to where your trouser is normally worn on the shoe.
Jacket Length: Measure from the centre back of your neck to your hemline. Then length measurement will vary depending on the style.
Feet: Use a ruler or tape measure to measure your foot (from the heel to the tip of your longest toe) Be sure to measure both feet. Many people have feet of different sizes. Fit to the larger of the two.
Worn this hat for three months now in Scotland now South Africa. The hat fits well and release clip at the back good and shades your eyes well. I believe it is water proof but hard to tell as you perspire so much, and that is just quick walking, and my head gets soaked. So breathability does not appear to be working for me.
Value for money, I would honestly say not in my experience