27 C.F.R. § 25.294
(b) The brewer shall make a record of inventories of beer or cereal beverage which will show the following:
(c) The brewer shall retain inventory records and make them available for inspection by an appropriate TTB officer.
(Sec. 201, Pub. L. 85-859, 72 Stat. 1390, as amended (26 U.S.C. 5415))
[T.D. ATF-224, 51 FR 7673, Mar. 5, 1986, as amended by T.D. TTB-91, 76 FR 5478, Feb. 1, 2011]