| 631 | Overload Relays | Company Product |
| 632 | Overvoltage Protection Devices | Company Product |
| 633 | Own Compost | Company Product |
| 634 | Own Email Address | Company Product |
| 635 | Ox | Company Product |
| 636 | Ox Optical | Company Product |
| 637 | Oxalic Acid | Company Product |
| 638 | Oxidizing Biocide | Company Product |
| 639 | Oximeter | Company Product |
| 640 | Oximetry | Company Product |
| 641 | Oxo Bio Trash Bags | Company Product |
| 642 | Oxo Biodegradable Garbage Bags | Company Product |
| 643 | Oxo Biodegradable Trash Bags | Company Product |
| 644 | Oxo Business | Company Product |
| 645 | Oxobusiness | Company Product |
| 646 | Oxy Acetylene Welding | Company Product |
| 647 | Oxyduo Dissolved Oxygen | Company Product |
| 648 | Oxyferm | Company Product |
| 649 | Oxygen | Company Product |
| 650 | Oxygen Analyser | Company Product |
| 651 | Oxygen Analysers | Company Product |
| 652 | Oxygen Analyzer | Company Product |
| 653 | Oxygen Bank | Company Product |
| 654 | Oxygen Dissolved | Company Product |
| 655 | Oxygen Dissolved Chemicals | Company Product |
| 656 | Oxygen Dissolved Level Meters | Company Product |
| 657 | Oxygen Gas Distributors | Company Product |
| 658 | Oxygen Gas Manufacturers | Company Product |
| 659 | Oxygen Generators | Company Product |
| 660 | Oxygen Level Sensors | Company Product |