| Business | Phone |
| Air Perfect 8640 Beck Ln, Manassas 20110 | (703) 361-3769 |
| Applied Mechanical Consulting 10100 Nokesville Rd, Manassas 20110 | (703) 369-5052 |
| Thomas Co 8106 Mace Ct, Manassas 20111 | (703) 396-9290 |
| Dynamic Systems Inc 10100 Nokesville Rd, Manassas 20110 | (703) 367-9067 |
| R M Mechanical 10100 Nokesville Rd, Manassas 20110 | (703) 331-1038 |
| Precision Mechanical 9203 Enterprise Ct, Manassas 20111 | (703) 368-3413 |
| Paramount Mechanical 7053 Gateway Ct, Manassas 20109 | (703) 369-1750 |
| Master Techs Inc 10405 Balls Ford Rd, Manassas 20109 | (703) 335-5777 |
| High Purity Systems 8432 Quarry Rd, Manassas 20110 | (703) 330-5094 |