| BasePen | Provide default properties of Pen |
| Pen | Pen is the basic class of a pen with all pen properties |
| PenConfigAdapter | The adapter for opensense plugin manager. |
| PenProps | Pen Property Bundle is used to store all key-value properties of a pen. |
| PenPropsDatabase | Common Database definition |
| PenUtils | Basic pen utility |
| ReadOnlyPenProps | Read-only pen properties. |
| PenException | Exception that occurs during handling pen |