| Trivolt |
| RDM |
| Tru-Temp |
| Prime |
| Star Electric |
| Wheelock |
| Grainger |
| Dolfamex |
| Scully-Jones |
| General Signal |
| Marcus Transformer of Canada |
| Container Inspection Systems |
| Superior Electric |
| Opcon |
| Minarik Electric Company |
| Zinsco |
| Rex Manufacturing |
| Thormag |
| Coil Tran. Inc. |
| Triad-Utrad |
| American Electronics Company |
| Trabon |
| National Controls Corporation |
| Nais |
| Maguire |
| S+S |
| Nelmor |
| Kunkle Industries |
| RKC Instrument |
| RKC |
| Endress+Hauser |
| LaRos Equipment Company |
| Edwards Signaling |
| Hartmann & Braun-Circant |
| Bell Electrical Products |
| Autonics |
| Woodhead |
| Reliasys |
| Webster |
| Sutorbilt |
