N.J. Stat. § 43:16A-4.1
Notwithstanding the provisions of section 4 of P.L. 1944, c. 255 (C. 43:16A-4) all persons presently employed as policemen by a borough having a population between 8,400 and 8,500 inhabitants according to the 1970 census, and located in a second-class county, which employment with said borough was terminated for a period of less than 4 years and who prior to said termination were members of the Police and Firemen's Pension Fund, shall be permitted to make contributions covering such a period of termination on the basis of rates established by the actuary, provided the respective borough makes the necessary employer contribution to the fund covering such period of termination on the basis of rates established by the actuary.
N.J.S. § 43:16A-4.1