The original Flexfit cap with our Sierra Nevadas logo. Flexfit uses a patented spandex weave that provides the perfect combination of durability and comfort. Flexfit caps feature a patented technology that weaves polyurethane spandex into the sweatband and throughout the entire crown, providing a superbly comfortable fit. The Wooly Combed Twill Flexfit Caps are also constructed with a Permacurv PE Visor to give it that rounded, athletic look and feel. Our visors come with a technology that keeps its proper shape and curve at all times. Signature synthetic material helps maintain the hats proper curve.