100% POLYESTER Quality Material: Captain trucker caps come with a piece of soft sponge on the front, and breathable mesh on the back, the brim is made of premium polyester, lightweight and comfortable to wear, won't make your head sweltering in hot summer Adjustable Size: Blank mesh hat is 4.7 inches in height, with a adjustable buckle behind, suitable for most men and women with a head circumference in 22.8-25.2 inches; the brim is 3 inches wide, effectively block the harmful sunlight or uv rays Notes: Recommended temperature and time for heat transfer printing, 220℃/428℉, 8 seconds; the color will remain bright even after repeated washing or sunning Multifunctional Hats: Unique gifts for yourself, your families or friends, to give your friends a surprise, you can also DIY with them together and share the fun; essentials for daily life and outdoor activities, such as running, baseball, hiking, riding, camping and more