27 C.F.R. § 24.170
(b) Testing instruments. The proprietor shall have ready access to equipment for determining the alcohol content unless the proprietor only receives and stores on wine premises bottled or packed wine with evidence showing the alcohol content has been determined. The proprietor who bottles or packs wine shall have ready access to equipment for determining the net contents of bottled or packed wine. The appropriate TTB officer may require other testing instruments based upon the proprietor's operations.
(Sec. 201, Pub. L. 85-859, 72 Stat. 1379, as amended, 1395, as amended (26 U.S.C. 5357, 5552))
(Approved by the Office of Management and Budget under control number 1512-0298)
[T.D. ATF-299, 55 FR 24989, June 19, 1990, as amended by T.D. ATF-409, 64 FR 13683, Mar. 22, 1999]