I am so impressed with this hat!  It is so versatile and well made.  I really like that I can fold it up or squash it, and it endures well.  I do all of my hard work in it and it really protects my head and neck well from the sun and heat and the vents do make a difference. The straps on it are brilliant too.  I ordered an x-large (i have a big head) and it is a comfy loose fit.  Even if I have my hair pulled into a pony tail, it is a great fit.