The NIJ (the U.S body) is considered the world leader for ballistic testing for armor, they perform a full range of tests and provide details of the results in their armor standards. These show the range of protection offered by the different pieces of armor tested, from low powered hand guns, up to armor piercing rifle rounds. They provide 8 classifications of protection known as threat levels which are Class I, IIA, II, IIIA, III, IV, V & VI.