Quick Take: ACR Electronics manufactures the $40 RapidFire inflatable PFD strobe light for safety-minded boaters. Designed to help rescue personnel locate overboard mariners, the RapidFire weighs a mere 2.8 ounces and attaches to any life vest. The strobe is activated automatically upon vest inflation; if yours is noninflatable, simply pull on the RapidFire's lanyard. The strobe flashes approximately 60 times per minute with a nominal visibility of up to two miles and can last up to eight hours in extreme (-4 degrees Fahrenheit) water conditions. This little yellow gizmo can help save your life if you find yourself overboard in the dead of night or in rough seas--so don't leave land without one.