| Business | Phone |
| Coffman Design Inc 1145 Hastings St, Traverse City 49686 | (231) 932-9767 |
| Grand Traverse Engineering Inc 6029 Robert Dr, Traverse City 49684 | (231) 267-9541 |
| Neddo Tooling & Engineering 7109 S Whispering Hills Dr, Traverse City 49684 | (231) 947-5776 |
| Steven J Dixon 836 Rose St, Traverse City 49686 | (231) 929-7005 |