Never forget where your sunglasses are again with the Bowline sunglass retainers from Costa Del Mar. Flexible, durable and lightweight, the Costa Bowline retainer is a streamlined silicone retainer with sliding bead for adjustable tension to make sure your sunglasses stay put, on and off the water. Costa products sold by authorized sellers, like Amazon, are eligible for all manufacturer warranties and guarantees. Visit the Costa shop by clicking on the brand link above to shop the entire Costa assortment.