1, primary file: generally for players who learn billiards or have low technical level. The rules are relatively simple, the club is light, the table is small, it is suitable for basic practice and easy to use.
2, intermediate file: generally suitable for people who are slightly familiar with the basic skills and rules of billiards. The club is slightly heavier, the table size is moderate, and the rules are relatively complicated, so you can practice some tactics.
3. Advanced file: Generally speaking, it refers to professional and top players. Clubs are heavier, tables are larger, rules are more complicated, and superb technical and tactical abilities are needed.