| Business | Phone |
| Independent Systems Analysis 5702 Industry Ln # A1, Frederick 21704 | (301) 694-5588 |
| Kaempf & Harris Sheet Metal 217 Monroe Ave # A, Frederick 21701 | (301) 663-6670 |
| Lease Brothers Sheet Metal Inc 4580 Mack Ave # B, Frederick 21703 | (301) 695-1254 |
| Tec Inc 5713 Industry Ln # 58, Frederick 21704 | (301) 663-4700 |