27 C.F.R. § 555.183
Importing plastic explosives
Persons filing a Form 6 application to import plastic explosives must attach to the application the following written statement executed under the penalties of perjury:
(a) “I declare under the penalties of perjury that the plastic explosive to be imported contains a detection agent as required by 27 CFR 555.180(b)”; or
(b) “I declare under the penalties of perjury that the plastic explosive to be imported is a “small amount” to be used for research, training, or testing purposes and is exempt from the detection agent requirement pursuant to 27 CFR 555.182.”