Description Sierra's timeless and flattering rounded P3 shape is a tribute to Revo's best-selling styles from the 1995 Classic and H2O Collections. Sierra blends lightweight acetate with advanced NASA-based polarized Crystal lens technology for sunglasses that not only look good, but feel even better. Sierra is a smaller fit and features a classic keyhole bridge with spring hinges to hold it comfortably in place. Revo's polarized Crystal lens technology enhances your view from scenic coastal drives to sunny mountain cabin porch swings to a round of golf while protecting from glare.