N.J. Stat. Ann. § 48:16A-6

Where a vehicle operates in more than one municipality, the insurance policy or bond required by sections 2 and 3 of this act shall be filed with the clerk of the municipality in which the owner has his principal place of business and certificates, in such number as may be necessary, certifying that the owner has complied with all the provisions of this act shall, by the clerk of the municipality, be delivered to the owner, who shall file the certificate with the clerk of each municipality in which such operation takes place.