This references existing OECD guidance on Due Diligence for Responsible Supply Chains and its various annexes.

Duties are established in respect of import quantities identified in Annex 1 some of which are quite low e.g.

-          Tin bars, rods, profiles and wires               1,400 Kg

-          Other tin articles                                              2,100 Kg

-          Tungsten wires                                                 250 Kg

Regulation text: http://eur-lex.europa.eu/legal-content/EN/TXT/?uri=CELEX:32017R0821