27 C.F.R. § 5.148 – Agave spirits.

(a) The class agave spirits. “Agave spirits” are distilled from a fermented mash, of which at least 51 percent is derived from plant species in the genus Agave and up to 49 percent is derived from other sugars. Agave spirits must be distilled at less than 95 percent alcohol by volume (190° proof) and bottled at or above 40 percent alcohol by volume (80° proof). Agave spirits may be stored in wood barrels. Agave spirits may contain added flavoring or coloring materials as authorized by § 5.155. This class also includes mixtures of agave spirits. Agave spirits that meet the standard of identity for “Tequila” or “Mezcal” may be designated as “agave spirits,” or as “Tequila” or “Mezcal”, as applicable.

(b) Types. Paragraphs (b)(1) and (2) of this section describe the types of agave spirits and the rules for each type.

Type	Standards
(1) Tequila	An agave spirit that is a distinctive product of Mexico. Tequila must be made in Mexico, in compliance with the laws and regulations of Mexico governing the manufacture of Tequila for consumption in that country.
(2) Mezcal	An agave spirit that is a distinctive product of Mexico. Mezcal must be made in Mexico, in compliance with the laws and regulations of Mexico governing the manufacture of Mezcal for consumption in that country.