To fit head (recommended): S 55cm (21.8"), M 57cm (22.5"), L 59cm (23.2"), XL 61cm (24"), XXL 62cm (24.4"). Made of 100% shrink-, fade-, and wrinkle-resistant Cotton fabric, the ACU US Field Cap from MFH features wide reinforced visor, internal map pocket, rear loop field for tags and serged internal seams for added comfort. Being an important part of military uniforms of armies across the globe and becoming one of the most fashionable trends, this robust MFH ACU US Field Cap is an excellent choice to all those who are searching for quality and classic headgear for work, everyday wear or any outdoor activities all year round.