Lifebuoy

Buoy designed to be thrown to person in water, to prevent drowning

A lifebuoy, life preserver, life ring, or lifesaver among many other names (see § Other names), is a life-saving buoy designed to be thrown to a person in water to provide buoyancy and prevent drowning. Some modern lifebuoys are fitted with one or more seawater-activated lights to aid rescue at night.

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