Each container of distilled spirits having a capacity of one gallon (3.785 liters) or less must have a closure or other device securely affixed to the container. The closure or other device must be constructed in such a manner as to require breaking in order to gain access to the contents of the container. (Sec. 454, Pub. L. 98-369, 98 Stat. 494 (26 U.S.C. 5301)) [T.D. TTB-119, 79 FR 17033, Mar. 27, 2014]