In Chemradar, UN Number Search allows users to acquire the transport information of dangerous goods or articles by entering a four-digit number or proper shipping name. It also provides transport labels, hazard class, packing group, and special provisions. United Nations (UN) Numbers are four-digit numbers used worldwide in international commerce and transportation to identify hazardous chemicals or classes of hazardous materials. UN numbers are unique identifiers specified by the Untied Nations Committee of Experts on the Transport of Dangerous Goods. Some hazardous substances have their own UN numbers (e.g. Acrylamide has UN 2074), while sometimes groups of chemicals or products with similar properties receive a common UN number (e.g. lighters and flammable gases, have UN 1057). A chemical in its solid state may receive a different UN number than the liquid phase if its hazardous properties differ significantly; substances with different levels of purity (or concentration in solution) may also receive different UN numbers.