If I may, we suggest saying item 18 because it refers to “Methamphetamine (N,a-dimethylbenzeneethanamine), its salts, derivatives, isomers and analogues and salts of derivatives, isomers and analogues”. It's sort of like methamphetamine and anything else that's pretty darn close to methamphetamine and does the same stuff, to put it in the kind of language I understand, as opposed to these various lists of drugs.
We didn't want a person to be able to say, “I wasn't producing methamphetamine, N,a-dimethylbenzeneethanamine; I added one little molecule of something else, so it wasn't quite meth.” That would be a salt or derivative or analogue.
So that's all it's doing.