We believe the Costa Del Mar Spearo 580G Polarized Sunglasses pair best with crystal-clear turquoise waters reflecting a bright, blue sky. Their polarized lenses deflect all those harsh rays, and they're made of 580G glass for superior clarity, scratch-resistance, and thin lightness. Costa made the frame out of a bio-based resin for an environmentally friendly construction that doesn't harm the beaches we love to relax on.