49 CFR § 172.523 - EXPLOSIVES 1.4 placard.
(a) Except for size and color, the EXPLOSIVES 1.4 placard must be as follows:
(b) In addition to complying with § 172.519 of this subpart, the background color on the EXPLOSIVES 1.4 placard must be orange. The “*” shall be replaced, when required, with the appropriate compatibility group letter. The division numeral, 1.4, must measure at least 64 mm (2.5 inches) in height. The text, numerals and inner border must be black.
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