Every permit shall be in two parts, namely Part A and Part B in the form as prescribed. One copy of Part B shall be issued in respect of every vehicle authorised by the permit and where the permit relates to more than one vehicle, each such copy shall contain, in addition to the number of the permits, a separate serial number contained in brackets after the number of permit. Each such copy shall be sealed and signed by the Authority by which the permit is issued and by the Authority by which the same is countersigned.