One of the biggest mistake is the choice of EAC CoC or EAC DoC procedure that is based on HS-code list.
Take a look at this sample that's why ...
It's great mistake to think that HS-code specified at CoC or DoC is very important or helpful because during customs clearance procedure a customs official have right to change it as they want. Because EAEU Customs regulation establishes the following rule (paragraph 4 of Article 20).
The HS-codes of goods specified in commercial, delivery and (or) other documents, as well as in conclusions, certificates, expertise acts issued by expert institutions are not mandatory for the goods classification which is performed by customs officials.
So don't waste your time to specify an HS-code exactly.