Provides that the Chief Constable may, when granting a certificate, attach conditions to it and that subsequently he may, by notice in writing, vary or revoke them. The powers of the Chief Constable include the power to restrict the types, numbers and quantities of firearms and ammunition which a dealer may hold. The Article gives the Secretary of State the power to give directions to the Chief Constable as to the conditions to be imposed, varied or revoked. In order to effect any of this the Chief Constable may require a dealer to produce his certificate to him and failure to do so may result in its revocation under Article 29.