N.J. Stat. § 45:14C-26
In addition to such other bonds as may be required pursuant to contract, no master plumber who is the holder of a license under the provisions of this act shall undertake to do any plumbing work in the State of New Jersey or any political subdivision thereof unless and until he shall have first entered into a bond in favor of the State of New Jersey in the sum of $3,000.00 executed by a surety company authorized to transact business in the State of New Jersey, approved by the Department of Banking and Insurance and to be conditioned on the faithful performance of the provisions of this act. No municipality shall require any similar bond from any master plumber licensed under this act. The board shall by rule and regulation provide who shall be eligible to receive the financial protection afforded by the bond required to be filed hereunder. The aforesaid bond shall be for the term of 12 months and shall be renewed at each expiration for a similar period.
N.J.S. § 45:14C-26