N.J. Stat. Ann. § 52:25-25

Agreements for purchases may be made in the form of contracts for the furnishing of specific articles at fixed prices, or for the furnishing of articles according to the specifications at a fixed rate with provision for a minimum amount subject to increase at the same rate or for the furnishing of articles according to specifications without a stated minimum or maximum at a rate stated, commonly known as the "price agreement" at the discretion of the commissioner.