| Business | Phone |
| S & R Technology Holdings 4801 Hampden Ln, Bethesda 20814 | (301) 656-5446 |
| Potomac Holdings Inc 5401 Bradley Blvd, Bethesda 20814 | (301) 986-8420 |
| Holding Jurie 7513 Wisconsin Ave, Bethesda 20814 | (301) 469-3040 |
| Horizon Development Holdings Bethesda 20817 | (301) 767-0970 |