| Deines-Nitz Solutions, LLC Milling, Finishing | Erie, IL | MillingFinishing | - |
| Demco Products Milling, Turning, Swiss, Finishing, Assembly · ISO 9001 | Oak Lawn, IL | MillingTurningSwissFinishingAssembly | ISO 9001 |
| Forge Resources Group Turning, Forging, Grinding, Finishing · ISO 9001, AS9100, ITAR | Dekalb, IL | TurningForgingGrindingFinishing | ISO 9001, AS9100, ITAR |
| Helander Metal Spinning Company LLC Milling, Turning, Laser, Waterjet, Welding, Stamping, EDM, Finishing · NADCAP | Lombard, IL | MillingTurningLaserWaterjetWeldingStampingEDMFinishing | NADCAP |
| Kris Dee and Associates, Inc Milling, Casting · ISO 9001, AS9100, ITAR | South Elgin, IL | MillingCasting | ISO 9001, AS9100, ITAR |
| Manufacture Design Innovation, Inc Milling, Turning, Welding | Gilberts, IL | MillingTurningWelding | - |
| Hennig Milling · ISO 9001, AS9100 | Rockford, IL | Milling | ISO 9001, AS9100 |
| American Machining Inc Milling, Turning, Welding, Grinding, Finishing · ISO 9001 | Ottawa, IL | MillingTurningWeldingGrindingFinishing | ISO 9001 |
| Anchor-Harvey Components LLC Milling, Forging, Finishing · ISO 9001, AS9100 | Freeport, IL | MillingForgingFinishing | ISO 9001, AS9100 |
| Avanti Engineering Inc Milling, Turning, Swiss, EDM, Grinding, Finishing, Assembly · ISO 9001 | Glendale Heights, IL | MillingTurningSwissEDMGrindingFinishingAssembly | ISO 9001 |
| Aztec Plastic Company Welding, Stamping, Grinding, Finishing, Assembly | Chicago, IL | WeldingStampingGrindingFinishingAssembly | - |
| Century Metal Spinning Co Milling, Turning, Laser, Bending, Welding, Finishing · ISO 9001, AS9100, ITAR | Bensenville, IL | MillingTurningLaserBendingWeldingFinishing | ISO 9001, AS9100, ITAR |
| Chem Processing Inc Finishing · ISO 9001, AS9100, ITAR, NADCAP | Rockford, IL | Finishing | ISO 9001, AS9100, ITAR, NADCAP |
| CM Fabrication, LLC Milling, Laser, Welding, Finishing | Sycamore, IL | MillingLaserWeldingFinishing | - |
| Dynomax Inc EDM, Finishing, Assembly · ISO 9001, AS9100, ITAR | Wheeling, IL | EDMFinishingAssembly | ISO 9001, AS9100, ITAR |
| EDM Intelligent Solutions Milling, EDM, Grinding · ISO 9001, ITAR | Bartlett, IL | MillingEDMGrinding | ISO 9001, ITAR |
| Foster Works LLC Laser, Punching, Bending, Welding, Stamping, Finishing | Chicago, IL | LaserPunchingBendingWeldingStampingFinishing | - |
| H3 Manufacturing Group LLC Laser, Bending, Welding, Finishing · ISO 9001 | Schaumburg, IL | LaserBendingWeldingFinishing | ISO 9001 |
| Jem Custom Products, Inc Milling, Finishing | Wauconda, IL | MillingFinishing | - |
| Krametech, Inc Milling, Finishing, Assembly | Lake Zurich, IL | MillingFinishingAssembly | - |
| M-1 Tool Works, Inc Milling, Turning, EDM, Grinding, Finishing, Assembly · ISO 9001, AS9100 | Mchenry, IL | MillingTurningEDMGrindingFinishingAssembly | ISO 9001, AS9100 |
| Magnetic Inspection Laboratory, Inc Milling, Welding, Finishing · ISO 9001, AS9100, NADCAP, ISO 13485 | Elk Grove Village, IL | MillingWeldingFinishing | ISO 9001, AS9100, NADCAP, ISO 13485 |
| Murphy Machine Products, Inc Milling, Turning, Swiss, Grinding, Finishing · ISO 9001 | Wood Dale, IL | MillingTurningSwissGrindingFinishing | ISO 9001 |
| Panek Precision Products LLC Milling, Turning, Stamping, Grinding, Finishing, Assembly · ITAR | Northbrook, IL | MillingTurningStampingGrindingFinishingAssembly | ITAR |
| Quadrant Tool and Manufacturing Company Milling, Turning, EDM, Grinding, Finishing | Schaumburg, IL | MillingTurningEDMGrindingFinishing | - |
| Quality Metal Products Inc Milling, Turning, Finishing | Peoria, IL | MillingTurningFinishing | - |
| R C Industries Inc Finishing | Chicago, IL | Finishing | - |
| R. A. Zweig, Inc Milling, Swiss, Finishing, Assembly | Glenview, IL | MillingSwissFinishingAssembly | - |
| Saporito Finishing Co Welding, Finishing · NADCAP | Cicero, IL | WeldingFinishing | NADCAP |
| Schmid Tool & Engineering Corp Milling, Turning, Swiss, Stamping, Grinding, Finishing, Assembly · ISO 9001, ITAR | Villa Park, IL | MillingTurningSwissStampingGrindingFinishingAssembly | ISO 9001, ITAR |
| Sonic Manufacturing Corporation Milling, Welding, EDM, Grinding, Finishing, Assembly · AS9100, NADCAP | Elk Grove Village, IL | MillingWeldingEDMGrindingFinishingAssembly | AS9100, NADCAP |
| Sycamore Precision, Inc Milling, Casting, Finishing | Genoa, IL | MillingCastingFinishing | - |
| Titan Metal Fabricators, Inc Welding, Finishing | Northbrook, IL | WeldingFinishing | - |
| Toolex Corp Milling, Welding, EDM, Grinding, Finishing | Addison, IL | MillingWeldingEDMGrindingFinishing | - |
| Walco Tool & Engineering Corp Milling, Turning, Welding, Grinding, Finishing · ISO 9001 | Romeoville, IL | MillingTurningWeldingGrindingFinishing | ISO 9001 |
| Wpa Works LLC Milling, Turning, Swiss, EDM, Finishing · ISO 9001 | Elgin, IL | MillingTurningSwissEDMFinishing | ISO 9001 |
| 360 Machine Shop Milling, Turning, Laser, Welding, Metal AM | Bloomington, IL | MillingTurningLaserWeldingMetal AM | - |
| 425 Manufacturing Milling, Turning, Welding, EDM · ISO 9001 | Rockford, IL | MillingTurningWeldingEDM | ISO 9001 |
| A.j.r. Industries, Inc Milling, Turning | Elk Grove Village, IL | MillingTurning | - |
| Accurate Metals Illinois Laser, Welding · ISO 9001 | Rockford, IL | LaserWelding | ISO 9001 |
| Ace of Diamonds International Inc Milling | Aurora, IL | Milling | - |
| Alanson Mfg L.L.C Turning, Finishing · ISO 9001, ITAR | Chicago, IL | TurningFinishing | ISO 9001, ITAR |
| Art CNC Machining LLC Milling, Turning, Assembly · ISO 9001 | Bridgeview, IL | MillingTurningAssembly | ISO 9001 |
| Astoria Wire Products Inc Milling, Laser, Punching, Bending, Welding | Bedford Park, IL | MillingLaserPunchingBendingWelding | - |
| Bennett Metal Products Inc Milling, Turning, Waterjet, Welding · ISO 9001, ITAR | Mount Vernon, IL | MillingTurningWaterjetWelding | ISO 9001, ITAR |
| Betts Precision, Inc Milling, Turning, EDM, Grinding · AS9100, ISO 13485 | Alsip, IL | MillingTurningEDMGrinding | AS9100, ISO 13485 |
| Calisota Parts, LLC Milling, Waterjet, Stamping, EDM | Frankfort, IL | MillingWaterjetStampingEDM | - |
| Camcraft Inc Milling, Turning, Grinding | Hanover Park, IL | MillingTurningGrinding | - |
| Carr Machine & Tool, Inc Milling, Grinding, Assembly · ISO 9001, ITAR, CMMC | Elk Grove Village, IL | MillingGrindingAssembly | ISO 9001, ITAR, CMMC |
| Cast Technologies Inc Casting | Peoria, IL | Casting | - |