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Sunday Afternoons says:
With a stylish silhouette, the Ultra Escape Boonie is UPF 50+ sun rated, so you know you’ll be protected wherever your adventures lead. A simple adjustable sizing system helps it fit just right and crushable packability so you can take it anywhere. Made using bluesign® certified fabric with a PFC-free water repellent finish on the main body, mesh, and wicking sweatband, Sunglass Lock™ keeps glasses in place when not on your face.