| Offsets | Name | Length | Format | Description | |
|---|---|---|---|---|---|
| 0 | SMF993COF | 4 | binary | Offset to class information from the beginning of record (including RDW). | |
| 4 | 4 | SMF993CLN | 2 | binary | Length of the class information. |
| 6 | 6 | SMF993CON | 2 | binary | Number of class information. |
| 8 | 8 | SMF993CPOF | 4 | binary | Offset to class period section from beginning of record (including RDW). |
| 12 | C | SMF993CPLN | 2 | binary | Length of the class period section. |
| 14 | E | SMF993CPON | 2 | binary | Number of period sections. |