CFR › Title 49 › Part 178 › §178.33b-249 CFR §178.33b-2Verified against eCFR.gov as of June 20, 2026View official text on eCFR.gov ↗Copy link(a)Single-trip inside containers.(b)The maximum capacity of containers in this class shall not exceed one liter (61.0 cubic inches). The maximum inside diameter shall not exceed 3 inches.