COSTA DEL MAR TEMPEST CR 39
($109; 800-447-3700; www.costadelmar.com)
Lens: CR 39, polarized (Rx-able)
CR 39 is a form of plastic lens material developed in the eighties for the optical industry. Easily Rx-able, it's lighter and more impact-resistant than glass, and, according to Costa del Mar, won't scratch or warp like a polycarbonate. CR 39 is a bit pricier, but because the material hasn't yet caught on with consumers, manufacturers aren't demanding top dollar. The Tempests are a great value for this kind of featherweight quality. Rose-tinted polarized lenses eliminate all glare off the water, providing good subaquatic depth perception.

MAUI JIM VOLCANO
($179; 800-848-3644; www.mauijim.com)
Lens: polarized glass (Not Rx-able)
By "water sports" we mean the full range of wet work, from surfing to kayaking to sailing. The Volcanoes are perfect for all encounters. (OK, maybe not a capsizing off Saint Kitts: one plunge and you're out 180 bucks.) The frames are simple and strong. But it's the lenses you're paying for: seven layers of optical genius. Polarizing film is sandwiched between two hand-ground glass lenses; the outer glass is treated with silver dioxide to eliminate reflective glare, and the inner lens has a similar antireflective coating that absorbs the bounce-back glare from the water. A waterproofing agent on both surfaces makes spray bead up so you can see who's watching you on the beach. Available in tints of gray or rose.