A personal flotation device with buoyancy designed to maintain flotation with the face out of the water.

Any personal floatation device that will keep an individual who has fallen off a vessel, above water long enough to be run over by it or another rescue craft.

A floatation vest designed to be capable of holding an unconscious person afloat in the water, with their face upward and away from the water. There are various types designed for different purposes; some formed out of hard foam, some need to be inflated by blowing into a small valve on the front and some fold-up and have an automatic gas bottle to inflate them as soon as they're immersed in water. See also Buoyancy Aid.

chaleco

a must have item with a whistle

an essential piece of gear

a very good idea