Ring buoy with a light on a cruise ship
A lifebuoy, ring buoy, lifering, lifesaver, life donut, life preserver or lifebelt, also known as a "kisby ring" or "perry buoy", is a life saving buoy designed to be thrown to a person in the water, to provide buoyancy and prevent drowning. Some modern lifebuoys are fitted with one or more seawater-activated lights, to aid rescue at night.
The lifebuoy is usually ring- or horseshoe-shaped and has a connecting line allowing the casualty to be pulled to the rescuer in a boat. They are carried by ships and are also located beside bodies of water that have the depth or potential to drown someone.
The UK Royal Life Saving Society considers lifebuoys unsuitable for use in swimming pools because throwing one into a busy pool could injure the such as the torpedo buoy
Guard approved lifebuoys, buoy