Costa’s 580 Polycarbonate provides high clarity, impact- and scratch-resistance along with lightweight all day wear-ability.Silver Copper Mirror Polarized is well-suited for environments with varying light such as stream fishing.Costa’s co-injected bio-based nylon frame material is both tough and durable, while offering a comfortable fit.100% polarization kills reflected glare and reduces eye strain.Built by hand and backed for life. Every pair of Costa Sunglasses includes a limited lifetime warranty.