| Business | Phone |
| Bradford Engineering 3 Washington Sq # 3, Haverhill 1830 | (978) 373-2396 |
| Christiansen & Sergi Inc 160 Summer St, Haverhill 1830 | (978) 373-0310 |
| Ram Engineering 160 Main St # 1, Haverhill 1830 | (978) 372-0449 |
| Merrimack Engineering Svc Inc 45 Carleton St, Haverhill 1832 | (978) 373-5721 |