We wanted an ultimate performance cap, so we crammed a bunch of our favorite technologies into the Eclipse. Our Convertible Ventilation(TM) system covers for sun protection and opens up when airflow is needed. The Clamshell Brim(TM) lets you stow it away in your back pocket or the farthest reaches of your suitcase. Ear-friendly design keeps you comfy until the end of the road.Clamshell BrimPacking made easy! Our Clamshell Brim allows you to safely fold your hat in half for compact packability.Mesh VentilationKeep your head cool and protected with our mesh ventilation.Tech Sweat LinerGenerous sweat band to pull moister away from you head leaving you cool and ready for whats around the next bend.Adjustable SizingPick your size, then fine-tune the fit with our exterior size adjuster.UPF 50+ Sun ProtectionIt's hard to beat the enjoyment of a day in the sun, unless it's a day spent in the shady pleasantness of a UPF 50+ hat.A rating of UPF 50+ is the highest sun protective rating achievable and means only 1/50th or less of UV rays are able to pass through, allowing you to diminish the sun, not the fun!3" folding Clamshell Brim(TM)UPF 50+ Certified Sun Rating (mesh vents not rated)Convertible Ventilation(TM)High performance wicking microfiber100% Recycled, Wicking FabricIntegrated Wicking Sweatband LinerAdjustable SizingEar-friendly ProfileDesigned in USA/ImportedPatent PendingWeight: 2.2 ounces/62.4 grams