1. PELICAN SABRELITE 2010 RECOIL See coral in all its Day-Glo dazzle, even if you're 100 feet down at twilight. The SabreLite uses a mirror to focus its beam in a tight column that pierces the darkest water. It's rated to a depth of 500 feet and burns for 50 hours on three C batteries. Bonus: A glow-in-the-dark cuff makes it easy to find after dusk. $65; www.pelican.com

2. SPYDERCO SALT 1 Salt water rusts standard knives as consistently as Tom Cruise embarrasses himself. Not so the Salt 1. Forged with a unique nitrogen-based steel that's rolled hard, without heat-treating, the knife's three-inch blade, as well as its folding and locking mechanisms, are impervious to corrosion from the sea. $78; www.spyderco.com

3. BODY GLOVE VAPOR EX Water-repellent boardshorts? Sounds about as necessary as butterproof toast. But the Vapor EX, with hydrophobic polyester fibers, absorbs less moisture in water and dries faster when out, reducing cling and chafing. That, plus two big cargo pockets, make the Vapor a good choice for tropical travel wear. $70; www.bodyglove.com

4. THE NORTH FACE PHILTER The Philter looks like a multisport kick, but open-air mesh uppers, as well as drain holes in both the bottom and one-piece insole/midsole, make it a true submersible. Water flows out like a sandal, but synthetic-nubuck reinforcements, a stable heel, and secure lacing provide this hybrid with light-hiker stability. $80; www.thenorthface.com