For men and women 18 years of age and older, with local, district and section championships, culminating in a national championship. NTRP levels include 2.5, 3.0, 3.5, 4.0, 4.5, 5.0, 5.5 and Open divisions. Team match format consists of two singles matches and three doubles matches, except for the 2.5, 5.0, 5.5 and Open divisions, which play one singles match and two doubles matches. Rosters for Adult League are limited to players with ratings at team level or 0.5 below team level, for e.g., a 3.0 may not join a 4.0 team. This rule does not apply to 5.5 or Open level teams.