The USBC Open Championships consists of team, doubles, singles, optional all-events and a Team All-Events category.
There are now three divisions, and the division for which you are eligible is based on your average or composite average of participants.
Regular - Any bowler whose average is above 209.
Standard - Any bowler whose average is between 181 and 209.
Classified - Bowlers who have a verifiable 180 or below average. Average verification is a must to compete in this division.
Excerpt from the USBC FAQ about new divisional breakdown for each event:
Divisions for team and doubles events will be based on a composite of the competitors' averages, with dome parameters for Standard and Classified teams:
Additional parameters for divisional placement:
1. Regular Division bowlers (entering averages of 210 and above) may not compete in Classified Team or Classified Doubles, regardless of composite average.
2. Teams in the Standard division may have no more than one bowler with an average of 210 or higher.
3. Teams in the Classified division may have no more than one bowler with an average between 181-209.