From Rutgers "University Regulations & Procedures Manual"
3.3.21 PROMOTION TO PROFESSOR OR EQUIVALENT RANKS
C. Within the rank of professor, the designation of Professor II is reserved for those faculty in the University (usually already in the rank of professor) who have achieved scholarly eminence in their discipline and fields of inquiry. The standard for promotion to Professor II is significantly higher than that applied in promotion to professor. The most significant area of consideration in determining promotion to Professor II for general teaching/research faculty is scholarship.... Only those faculty who have demonstrated outstanding achievement in [that area] by earning significant recognition inside and outside the University are eligible for promotion to Professor II. Typically, such recognition is reflected in national and international reputation in one's discipline. Teaching and service also apply to the general evaluation of a candidate for promotion to Professor II. A candidate for promotion to Professor II should be an exemplary member of the University faculty who consistently has demonstrated a high standard of achievement in all professorial roles.