When bottled, every label must have an Appellation of Origin (or Norma Oficial Registratrada Mexicana – NOM), and four numbers designating the distillery from which it was produced. The front label will also give the size of the bottle, the proof, and the category of the tequila (blanco, resposado, añejo, or extra añejo). If it is 100% agave, it must also say so on the front label and be bottled in Mexico (Hecho en Mexico).