| Business | Phone |
| Captive-Aire Systems Inc 4111 Bowen Rd, Toledo 43613 | (419) 474-6953 |
| Engineering Cad Svc 5353 Secor Rd, Toledo 43623 | (419) 472-1222 |
| Polytech Inc 101 Main St, Toledo 43605 | (419) 698-7675 |
| Patriot Engineering 3025 E Manhattan Blvd, Toledo 43611 | (419) 727-1525 |