Great for any time of the year, in the absence of extreme conditions.
The entirety of the brim is turned up designed to remain in this position, never "snapped" down.
Hat Sizing Guide
|XS||S||M||L||XL||XXL||One Size (OS)*|
|Inches||21¼||21⅝||22½||23¼||24||24⅞||21⅝ - 24|
|US Sizes||6¾||6⅞||7⅛||7⅜||7⅝||7⅞||6⅞ - 7⅝|
|UK Sizes||6⅝||6¾||7||7¼||7½||7¾||6¾ - 7½|
*For baseballs currently: a 4-snap-in back strap means the size range is 55cm-61cm with 58cm as the center