A member of Coast Guard Station Rio Vista exhibits a Distress Signal Light (Firefly) during rescue and survival training, Friday, April 6, 2012. The distress signal light is a compact strobe light that gives 50-70 flashes per minute with the luminous intensity of 100,000-candle power and can last up to nine hours continuously or 18 hours intermittently. U.S. Coast Guard photo by Petty Officer 2nd Class Levi Read.