27 CFR § 5.203 - Standards of fill (container sizes).
(a) Authorized standards of fill. The following metric standards of fill are authorized for distilled spirits, whether domestically bottled or imported:
(1) Containers other than cans. For containers other than cans described in paragraph (a)(2) of this section—
(i) 1.8 Liters.
(ii) 1.75 Liters.
(iii) 1.00 Liter.
(iv) 900 mL.
(v) 750 mL.
(vi) 720 mL.
(vii) 700 mL.
(viii) 375 mL.
(ix) 200 mL.
(x) 100 mL.
(xi) 50 mL.
(2) Metal cans. For metal containers that have the general shape and design of a can, that have a closure that is an integral part of the container, and that cannot be readily reclosed after opening—
(i) 355 mL.
(ii) 200 mL.
(iii) 100 mL.
(iv) 50 mL.
(b) Spirits bottled using outdated standards. Paragraph (a) of this section does not apply to:
(1) Imported distilled spirits in the original containers in which entered into customs custody prior to January 1, 1980 (or prior to July 1, 1989 in the case of distilled spirits imported in 500 mL containers); or
(2) Imported distilled spirits bottled or packed prior to January 1, 1980 (or prior to July 1, 1989 in the case of distilled spirits in 500 mL containers) and certified as to such in a statement signed by an official duly authorized by the appropriate foreign government.