33 companies
| Ticker | Name | FYE |
|---|---|---|
| CECO | CECO ENVIRONMENTAL CORP | Dec 31 |
| DCI | DONALDSON Co INC | Jul 31 |
| FTEK | FUEL TECH, INC. | Dec 31 |
| KNOS | KRONOS ADVANCED TECHNOLOGIES INC | Jun 30 |
| MAIR | Madison Air Solutions Corp | Dec 31 |
| PPIH | Perma-Pipe International Holdings, Inc. | Jan 31 |
| PIAC | PRINCETON CAPITAL CORP | Dec 31 |
| ADVANCE ROSS CORP | Dec 31 | |
| BARE METAL STANDARD INC. | Oct 31 | |
| BHA GROUP INC | Sep 30 | |
| CADEMA CORP | Dec 31 | |
| CDTI ADVANCED MATERIALS, INC. | Dec 31 | |
| CROWN ANDERSEN INC | Sep 30 | |
| EARTH SCIENCES INC | Dec 31 | |
| ENVIRONMENTAL ELEMENTS CORP | Mar 31 | |
| E/S CORP | ||
| FAIRFIELD MANUFACTURING CO INC | Dec 31 | |
| Filtration Group Corp | Dec 31 | |
| FLAIR CORP | Mar 28 | |
| FLANDERS CORP | Dec 31 | |
| GREAT AMERICAN MANAGEMENT & INVESTMENT INC | Jun 30 | |
| IONIC FUEL TECHNOLOGY INC | Jun 30 | |
| MET PRO CORP | Jan 31 | |
| MIDWESCO FILTER RESOURCES INC /IL | Jan 31 | |
| Molekule Group, Inc. | Dec 31 | |
| PACIFIC ALLIANCE CORP | Dec 31 | |
| PFEIFFER VACUUM TECHNOLOGY AG | Dec 31 | |
| PLANET TECHNOLOGIES, INC | Dec 31 | |
| PYURE Co INC. | Dec 31 | |
| TRION INC | Dec 31 | |
| UNITED AIR SPECIALISTS INC /OH/ | Jun 30 | |
| UV FLU TECHNOLOGIES INC | Sep 30 | |
| WUHAN GENERAL GROUP (CHINA), INC | Dec 31 |