| Business | Phone |
| Capital Lighting & Supply Inc 19050 Woodfield Rd, Gaithersburg 20879 | (301) 921-4446 |
| Central Electric Supply Ltd 7431 Lindbergh Dr, Gaithersburg 20879 | (301) 869-4470 |
| Dominion Electric Supply Co 16608 Oakmont Ave, Gaithersburg 20877 | (301) 948-7924 |
| Electronic Systems Svc 7901 Beechcraft Ave # N, Gaithersburg 20879 | (301) 924-6540 |
| Hitachi High-Tech America Inc 940 Clopper Rd, Gaithersburg 20878 | (301) 840-1650 |