| Business | Phone |
| Landis & Staefa Inc 6901 Muirkirk Meadows Dr, Beltsville 20705 | (301) 210-5025 |
| Siemens Building Technologies 6901 Muirkirk Meadows Dr, Beltsville 20705 | (301) 419-2600 |
| William E Kingswell Inc 5320 Sunnyside Ave, Beltsville 20705 | (301) 937-1900 |