The LeMieux Mesh Hat Silk is quartered with strategically placed mesh inserts for breathability to prevent hat vents from being blocked.Made from silky smooth 4-way stretch fabric, this hat cover is designed to fit over most helmet sizes for a snug and secure crease-free fit. It comes with a removable faux fur pom pom plus a interchangeable press stud so you can match it to your style. LeMieux Mesh Hat Silk - Thyme