Provides that the Chief Constable may vary a firearm certificate on the application by the holder, on payment of the appropriate fee. If the variation is for an additional firearm or ammunition it will attract the grant provisions of Article 5. A new provision enables a firearms dealer to vary a firearm certificate where the holder is seeking to replace a shotgun with another shotgun, a transaction commonly referred to as a “one for one”. Both parties are required, under Article 40, to advise the Chief Constable of the details of the variation within 72 hours. There is no fee for this type of transaction.