| # | Name | Location | Applications |
|---|---|---|---|
| 1. | Duh-Socket, Inc. | 🇺🇸 San Antonio, TX, United States | 1 |
| 2. | Duhaime Incorporated | 🇺🇸 Independence, MN, United States | 1 |
| 3. | DUHANBIO CO., LTD. | 🇰🇷 Seoul, South Korea | 1 |
| 4. | Duhn Oil Tool, Inc. | 🇺🇸 Bakersfield, CA, United States | 6 |