Size: L/XL Been looking at getting a hat for running and walking etc for some time. At present using generic trucker caps which are not ideal due to sweating etc. and do not wash very well. Just received this and used on morning run and first impressions are very good. I was not sure on size and didn’t measure my head so opted for the L/XL and fits fine. There is adequate adjustment at the back of the cap to cater etc. The fit is definitely different to what I am used to but is secure and the cap is very flexible it can be moulded to your head. The looks of the cap are not as good as my trucker cap but the performance is so much better. No issues noted with staining or going hard. After first wear I washed in the machine as per the instructions on low temp wash with other sports gear and came out perfect and now smells amazing and kept its shape. Would recommend to anyone who is undecided if to get as I have ruined many of my non-sports caps through exercising in them.