Buyer's Guide
| Company | Location | Company Type |
|---|---|---|
| O2TUBE TECHNOLOGIES INC. | BATAVIA, Illinois, United States | Manufacturer |
| O3 Water Systems, Inc | Cle Elum | Manufacturer |
| Oetiker, Inc | Marlette | Manufacturer |
| Ogden Manufacturing Co. | Pittsburgh | Manufacturer |
| Ogontz Corp. | Manufacturer | |
| Oil-Rite Corp. | Manitowoc | Manufacturer |
| Omexell, Inc. | Houston | Manufacturer |
| Omnipure Filter Co. | Caldwell, Idaho, United States | Manufacturer |
| Opella, Inc. | Marietta | Manufacturer |
| Orival, Inc. | Englewood | Manufacturer |
| Osmosis Techonology, Inc/Osmotik | Buena Park | Manufacturer |
| Ozone Pure Water | LEANDER | Manufacturer |
| Ozonology Inc. | Northbrook, Illinois, United States | Manufacturer |
| Ozotech, Inc. | Yreka | Manufacturer |
