What type of flotation device must be carried on a vessel 16 foot or longer?

In the United States, boats that are 16 feet long or over must be equipped with one Type IV PFD (as classified by the United States Coast Guard) per boat. A Type IV PFD is a throwable floating device; whether the classic "lifebuoy" or "lifesaver" type round version, or the square cushion-like type that are placed on the seats of recreational craft.