Now here’s a safety instrument that could literally be a lifesaver: Position fixes for sailors gone overboard are terrific, but nothing beats actually seeing the person in the water. Flares are a good way to attract attention, but very few of us carry them at all times. But the 10-inch Odeo Laser Flare, shaped like a flashlight, is a fine substitute. The waterproof Odeo MK2 attaches to a PFD. Unlike flares, which burn for an average of 30 seconds, the Odeo remains lit for five hours.