Where a rule in the list specifies that a product must be manufactured from a particular material, the condition does not prevent the use of other materials which, because of their inherent nature, cannot satisfy the rule.
Nuair a shonraítear faoi riail sa liosta nach mór táirge a mhonarú as ábhar ar leith, ní chuirtear cosc leis an gcoinníoll sin, ar ábhair eile a úsáid, ábhair nach féidir an riail a chomhlíonadh de bharr chineál bunúsach na n-ábhar sin.