Performance 1) Work time: > 2 hours 2) Self-operated with dipping into water 3) Luminous intensity: >2.0cd 4) Floated in water with self-buoyancy Application field 1) For Buoy ring as mandatory requirement by SOLAS 2) Night time flasher positioning in water for below case: a) for downing people to find the rescue position b) for rescue personnel to find downing people 3) for sea, river ship navigation