| Section No. | Description |
|---|---|
| Section 310.1 | Unlawful carriage of letters |
| Section 310.2 | Exceptions |
| Section 310.3 | Responsibility of carriers |
| Section 310.4 | Payment of postage on violation |
| Section 310.5 | Advisory opinions |
| Section 310.6 | Amendment of regulations |
| Section 310.7 | Definitions |