Costa named these C-Mates Bifocal Readers Fisch sunglasses for the famous adventurer and ocean lover, Chris Fischer. The full-rim frames are made in bio-based nylon, an eco-friendly plant-based resin that’s lightweight, durable, and retains its shape in extreme conditions. A three-hole ventilation system in the rims allows natural airflow to prevent the lenses from fogging up when you sweat. The skull temples curve inward for stability behind the ears, and feature a patented Hydrolite rubber lining for non-slip grip. The signature Costa C on the temples adds sporty appeal. Enjoy the convenience of bifocals on your outdoor adventures wearing these C-Mates Fisch shades from Costa.