| 631 | Oil Drilling Equipment | Company Product |
| 632 | Oil Well Drill Bits | Company Product |
| 633 | Oil Spill Dispersants | Company Product |
| 634 | Optical Brighteners Detergent | Company Product |
| 635 | Oil Mist Detectors | Company Product |
| 636 | Office Cupboards | Company Product |
| 637 | Overhead Travelling Cranes | Company Product |
| 638 | Oil Coolers | Company Product |
| 639 | Overhead Chain Conveyors | Company Product |
| 640 | Oil Discharge Controls | Company Product |
| 641 | Odour Controls | Company Product |
| 642 | Oil Pollution Controls | Company Product |
| 643 | Office Renovation | Company Product |
| 644 | Oil Drilling Contractors | Company Product |
| 645 | Oil Consultants | Company Product |
| 646 | Optical Comparators | Company Product |
| 647 | Offset, Photo Engraving Colour Separation | Company Product |
| 648 | Oil Circuit Breakers | Company Product |
| 649 | Orthodox Catholic Churches | Company Product |
| 650 | Oilfield Chokes | Company Product |
| 651 | Oilfield Chemicals | Company Product |
| 652 | Oil Drilling Chemicals | Company Product |
| 653 | Office Chairs | Company Product |
| 654 | Ordinary Portland Cement | Company Product |
| 655 | Oil Well Cement | Company Product |
| 656 | Oilwell Cementing | Company Product |
| 657 | Oil Well Cementing Equipment | Company Product |
| 658 | Oil & Gas Well Casings | Company Product |
| 659 | Oscilloscope Calibrators | Company Product |
| 660 | Office Filing Cabinets | Company Product |