The brewer shall accurately and reliably measure the quantity of beer transferred from the brewery cellars for bottling and for racking. The brewer may use a measuring device, such as a meter or gauge glass, or any other suitable method.
27 C.F.R. § 25.41
Sec. 201, Pub. L. 85-859, 72 Stat. 1395, as amended ( 26 U.S.C. 5552 )