Costa Squall/Grey Boga 580P Sunglasses Comfortable large fit, Optical spring hinge, Heavy-duty TR 90 nylon frame. Includes hard case, 100% UV light blockage for max protection. 100% polarization kills reflected glare and reduces eye strain. 100% polarization kills reflected glare and reduces eye strain. Plastic lenses are lightweight, impact- and scratch-resistant, Glass lenses have the greatest clarity and are scratch resistant.