| Business | Phone |
| Tech-Line Engineering Co 27560 College Park Dr, Warren 48088 | (586) 445-2500 |
| Sps Cad 28760 Walker Ave, Warren 48092 | (586) 558-4566 |
| Crown Design Inc 24525 Forterra Dr, Warren 48089 | (586) 759-0485 |
| D & S Design Svc Inc 21054 Ryan Rd, Warren 48091 | (586) 756-0640 |
| Dalco Design 24727 Gibson Dr, Warren 48089 | (586) 754-8138 |
| Expert Design Svc Inc 32480 Mound Rd A, Warren 48092 | (586) 977-9104 |
| Guelph Tool 24150 Gibson Dr, Warren 48089 | (586) 755-3333 |