Made of Polyester & Sponge Mixed Fabrication Front with Mesh Back, Lightweight & Breathable, the Moisture-permeable Mesh Keeps You From Getting Overheated, the Sponge Front Piece on the Front, Which You Can Diy in the Blank Space. Designed with an Adjustable Plastic Snap Closure, the Trucker Cap Fits Most Men & Ladies, Head Circumference is About 21.3-22.84 Inches, Offer a Flexible Fit to Your Head. Provided for Various Bright Colors, You Can Freely Choose the Colors You Like. Fashionable Back Mesh Baseball Caps Are Suitable for Daily Use, Camping, Cycling, Jogging, Climbing, Golf, Fishing, or for Trip, Music Festival & Other Outdoor Activities. Also It Can be Customized with Various Patterns as a Gift to Your Friends, Family Members.