Costa Del Mar Hammerhead Sunglasses — If you have the guts, you can swim with them. (The sharks, that is.) If you just want style and max coverage, wear these. Built around stainless steel spring hinges, these full-wrap, nylon frames come in any number of toothy colors. Go ahead, jump in.A comfortable Extra-Large fit.Stainless steel 5-barrel optical 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.Built by hand and backed for life. Every pair of Costas include a lifetime warranty.Plastic lenses are lightweight, impact- and scratch-resistant.Glass lenses have the greatest clarity and are scratch resistant.