N.J. Stat. § 40:69A-83.3
Any municipality adopting a council-manager plan of government may provide in its charter that the council members elected at the first regular municipal election or general election, as the charter shall provide, following the adoption of the plan shall serve for the following terms: if the municipal council is to consist of five members, two shall serve for four years and three for two years; if the municipal council is to consist of seven members, three shall serve for four years and four for two years; or if the municipal council is to consist of nine members, four shall serve for four years and five for two years. The length of the respective term of each member of the first council shall be determined by lot at the organization of the council immediately following the election; except that if, pursuant to the charter, the mayor is elected directly by the voters, the mayor shall, for the purposes of this subsection, be counted among those first council members to serve a four year term.
N.J.S. § 40:69A-83.3