| PTPorter Tire Center INC | Olive Hill | KY | — | ◇ UNVERIFIED |
| PEPowerhouse Equipment | Gastonia | NC | — | ◇ UNVERIFIED |
| PPPower Products and Engineering, LLC | Trenton | NJ | — | ◇ UNVERIFIED |
| PBPrecision Blend Gases, INC. | Dickinson | TX | — | ◇ UNVERIFIED |
| PMPrecision Micro Components | Redwood City | CA | — | ◇ UNVERIFIED |
| RBRentech Boiler Services INC | Abilene | TX | — | ◇ UNVERIFIED |
| RCRichardson Cooling Packages, LLC | New Castle | PA | — | ◇ UNVERIFIED |
| RPRiley Power INC | Gallatin | TN | — | ◇ UNVERIFIED |
| RPRiley Power INC | Worcester | MA | — | ◇ UNVERIFIED |
| RERite Engineering & Mfg CORP | Downey | CA | — | ◇ UNVERIFIED |
| RRR.J.R. Radiator, Inc. | Cincinnati | OH | — | ◇ UNVERIFIED |
| RTRocore Thermal Systems LLC | Burkesville | KY | — | ◇ UNVERIFIED |
| RCRp/presidio Central Campus Own | Santa Clara | CA | — | ◇ UNVERIFIED |
| SSSanmina - Sci | Newark | CA | — | ◇ UNVERIFIED |
| SFSchwabel Fabricating Com INC | Tonawanda | NY | — | ◇ UNVERIFIED |
| SPSheco Plant 2 | Tuscaloosa | AL | — | ◇ UNVERIFIED |
| SESmithco Engineering INC | Tulsa | OK | — | ◇ UNVERIFIED |
| STSo-semi Technologies Dba Optopax | San Jose | CA | — | ◇ UNVERIFIED |
| SHSouthern Heat Exchanger | Tuscaloosa | AL | — | ◇ UNVERIFIED |
| S2Spamex 2, LLC | Hartford | WI | — | ◇ UNVERIFIED |
| SHSpx Heat Transfer INC. | Tulsa | OK | — | ◇ UNVERIFIED |
| SHSpx Heat Transfer INC / Steel Products Fabrication | Tulsa | OK | — | ◇ UNVERIFIED |
| SMStead Motors | Walnut Creek | CA | — | ◇ UNVERIFIED |
| SBSterling Boiler & Mechanical, INC. | Parrish | FL | — | ◇ UNVERIFIED |
| SBSterling Boiler & Mechanical, INC. | Gallatin | TN | — | ◇ UNVERIFIED |
| SHSuperior Holding INC | Hutchinson | KS | — | ◇ UNVERIFIED |
 Swanson Industries, INC | Madisonville | KY | — | ◇ UNVERIFIED |
| TCTank Construction & Engineering INC | Fresno | CA | — | ◇ UNVERIFIED |
| TCTechnotherm CORP. | Tulsa | OK | — | ◇ UNVERIFIED |
| TCTei Construction Services, INC. | Royersford | PA | — | ◇ UNVERIFIED |
| TLTerex Light Contruction | Rock Hill | SC | — | ◇ UNVERIFIED |
 Thermal Engineering International (usa), INC. a Subsidary of Babcock Power | Sapulpa | OK | — | ◇ UNVERIFIED |
| TLThermamasters, LLC. | Wetumpka | AL | — | ◇ UNVERIFIED |
| TCThermasys Corporation | Iron Ridge | WI | — | ◇ UNVERIFIED |
| TSTriple S & P, INC. | Duette | FL | — | ◇ UNVERIFIED |
| TSTru Sheet Metal, INC. | Ronkonkoma | NY | — | ◇ UNVERIFIED |
| THTulsa Heaters, INC. | Tulsa | OK | — | ◇ UNVERIFIED |
| T3Turbo 3d LLC Dba Fugo | Gardena | CA | — | ◇ UNVERIFIED |
| TPTurbotec Products INC. | Windsor | CT | — | ◇ UNVERIFIED |
| UAUltratech a Division of Veeco | San Jose | CA | — | ◇ UNVERIFIED |
| UIUltratech, INC | San Jose | CA | — | ◇ UNVERIFIED |
| UCUnifin Chesapeake | Chesapeake | VA | — | ◇ UNVERIFIED |
| UDUniversal Dynamics | Woodbridge | VA | — | ◇ UNVERIFIED |
| UAUS Army Garrison West Point | West Point | NY | — | ◇ UNVERIFIED |
| UAUss Annapolis - Cal. Marine | San Diego | CA | — | ◇ UNVERIFIED |
| VPVapor Power International | Franklin Park | IL | — | ◇ UNVERIFIED |
| VHVolcanic Heater, INC. | Alliance | OH | — | ◇ UNVERIFIED |
| VFVulcan Finned Tubes L.p. | Tomball | TX | — | ◇ UNVERIFIED |
| WFWatts Fort Worth | Fort Worth | TX | — | ◇ UNVERIFIED |
| WWWatts Water Technologies INC | Hudson | MI | — | ◇ UNVERIFIED |
| WIWcr, INC. | Macon | GA | — | ◇ UNVERIFIED |
| WIWcr Incorporated | Fresno | CA | — | ◇ UNVERIFIED |
| WIWcr Incorporated | Seward | NE | — | ◇ UNVERIFIED |
| WCWebster Combustion Technology, LLC (stormwater) | Winfield | KS | — | ◇ UNVERIFIED |
| WIWellons INC | Sherwood | OR | — | ◇ UNVERIFIED |
| WMWickes Mfg CO | Beardstown | IL | — | ◇ UNVERIFIED |
| WDWilliams & Davis Boilers | Hutchins | TX | — | ◇ UNVERIFIED |
