| Business | Phone |
| Armstrong Engineering Svc Inc 720 Armstrong Dr, Buffalo Grove 60089 | (847) 215-7757 |
| John Fh Walker Inc 242 Anthony Ct, Buffalo Grove 60089 | (847) 541-2764 |
| Product Engineering Inc 718 Old Post Rd, Buffalo Grove 60089 | (847) 392-1063 |
| Northwestern Engineering 1110 W Lake Cook Rd 335, Buffalo Grove 60089 | (847) 520-8410 |
| Technical Loss Svc 1645 Barclay Blvd, Buffalo Grove 60089 | (847) 509-0660 |
| Wendes Systems 1130 W Lake Cook Rd 185, Buffalo Grove 60089 | (847) 808-8371 |