Scuba Diving Adventures Lost at Sea Help the Searchers!
Military, rescuers and commercial vessels, including high flying commercial flights will all respond to an SOS if they see it, if fact, are required by maritime law and tradition to respond if it does not put them or their ships in danger. With the long burn time of a LED you should get one maybe even two nights or more out of the batteries. A light turned on pointing at a boat in the day time can be seen for a long way off, and when the batteries die you can use it as a mirror to flash people a long way off to bring attention to you including planes and helicopters.