| # | Name | Location | Applications |
|---|---|---|---|
| 1. | GRK CANADA LIMITED | 🇨🇦 Thunder Bay, Ontario, Canada | 1 |
| 2. | GRK Canada Limited | 🇨🇦 Thunder Bay, Canada | 1 |
| 3. | GRK Canada Limited | 🇨🇦 Ontario, Canada | 1 |
| 4. | GRK CANADA LTD | 🇨🇦 Thunder Bay, Ontario, Canada | 1 |
| 5. | GRK Canada Ltd. | 🇨🇦 , Canada | 1 |
| 6. | GRK Canada Ltd. | 🇨🇦 Thunder Bay, Canada | 1 |
| 7. | GRK Manufacturing Co. | 🇺🇸 Hamilton, OH, United States | 1 |
| 8. | GRK Manufacturing Company | 🇺🇸 Cincinnati, OH, United States | 1 |
| 9. | GRK MANUFACTURING COMPANY | 🇺🇸 Hamilton, OH, United States | 4 |