Costa Caldera Net Gray With Blue Rubber Frame 580G Polarized SunglassesProduct Description. Born On The Water and named after a Central Chilean seaport, the Costa Polarized Caldera sunglasses are a large frame with a softly marked tumbled finish, elegant curves and uniquely textured temples with interior rubber temple grips for comfort + performance.. Nets that were once used to entangle fish, now protect your eyes, traveling full circle to produce a positive impact on our planet. These frames are made from 100% recycled