| Clark Metal Products Co Milling, Laser, Punching, Bending, Welding, Finishing, Assembly · ISO 9001 | Blairsville, PA | MillingLaserPunchingBendingWeldingFinishingAssembly | ISO 9001 |
| Classic Engineering, LLC Milling, Turning, Waterjet, Welding, Finishing | Gloucester, MA | MillingTurningWaterjetWeldingFinishing | - |
| Classic Metal Finishing, Inc Milling, Swiss, Grinding, Finishing, Assembly · ISO 9001, AS9100, ITAR, NADCAP | Jackson, MI | MillingSwissGrindingFinishingAssembly | ISO 9001, AS9100, ITAR, NADCAP |
| Clinkenbeard & Associates Inc Milling, Casting, Assembly · AS9100, ITAR | South Beloit, IL | MillingCastingAssembly | AS9100, ITAR |
| Clint Precision Manufacturing Milling, Turning, Welding, Waterjet · ISO 9001 | San Diego, CA | MillingTurningWeldingWaterjet | ISO 9001 |
| CM Manufacturing Inc Milling, Turning · ISO 9001, AS9100, ITAR | Missoula, MT | MillingTurning | ISO 9001, AS9100, ITAR |
| CMJ Manufacturing, Inc Milling, Turning, Grinding · AS9100 | Mulvane, KS | MillingTurningGrinding | AS9100 |
| CNC Industries, LLC Milling, Turning, Finishing, Assembly · ISO 9001, AS9100, ITAR | Fort Wayne, IN | MillingTurningFinishingAssembly | ISO 9001, AS9100, ITAR |
| CNC Innotech LLC Milling, Turning, Swiss | Ogdensburg, NJ | MillingTurningSwiss | - |
| CNC Machining & Engineering Inc Milling, Turning, Swiss | Ontario, CA | MillingTurningSwiss | - |
| CNC Manufacturing Corp Milling, Turning, Swiss · ISO 9001, AS9100 | Long Is City, NY | MillingTurningSwiss | ISO 9001, AS9100 |
| CNC Manufacturing Inc Milling, Turning, Swiss, Laser, Grinding · ISO 9001 | Coatesville, PA | MillingTurningSwissLaserGrinding | ISO 9001 |
| CNC Specialties Manufacturing Inc Milling, Turning, Bending, Welding, EDM, Grinding, Finishing | Apollo, PA | MillingTurningBendingWeldingEDMGrindingFinishing | - |
| CNCEdge Milling, Turning · ISO 9001 | Syracuse, NY | MillingTurning | ISO 9001 |
| Coanda Company LLC, the Milling, Turning, Waterjet, Welding · ISO 9001, AS9100 | Shawnee, OK | MillingTurningWaterjetWelding | ISO 9001, AS9100 |
| Coast Aerospace Manufacturing, Inc Milling, Welding · AS9100, ITAR | Placentia, CA | MillingWelding | AS9100, ITAR |
| Coffeyville Sektam, Inc Milling, Turning, Welding, Grinding, Assembly | Coffeyville, KS | MillingTurningWeldingGrindingAssembly | - |
| Colburn Manufacturing Company Milling, Turning · ISO 9001, ISO 13485 | Fridley, MN | MillingTurning | ISO 9001, ISO 13485 |
| Collins Manufacturing Inc Milling, Turning, EDM · ITAR | Essex, MA | MillingTurningEDM | ITAR |
| Columbia Asc Inc Milling, Turning, Laser, Waterjet, Bending, Welding, Stamping, EDM · ISO 9001 | Lawrence, MA | MillingTurningLaserWaterjetBendingWeldingStampingEDM | ISO 9001 |
| Combs Enterprises Incorporated Milling, Turning, Bending, Welding, Finishing · ITAR | Great Mills, MD | MillingTurningBendingWeldingFinishing | ITAR |
| Commercial Metal Fabricators, Inc Milling, Turning, Laser, Waterjet, Punching, Bending, Welding | Dayton, OH | MillingTurningLaserWaterjetPunchingBendingWelding | - |
| Commercial Tool & Die Inc Milling, Turning, Welding, Grinding | Marshall, VA | MillingTurningWeldingGrinding | - |
| Competitive Engineering, Inc Milling, Turning, EDM, Grinding, Assembly · AS9100 | Tucson, AZ | MillingTurningEDMGrindingAssembly | AS9100 |
| Compucraft Fabricators Inc Milling, Turning, Laser, Punching, Bending, Welding, Grinding, Finishing · ISO 9001, ITAR | Montgomeryville, PA | MillingTurningLaserPunchingBendingWeldingGrindingFinishing | ISO 9001, ITAR |
| Computer Assisted Manufacturing Technology LLC Milling, Assembly · ISO 9001 | Irvine, CA | MillingAssembly | ISO 9001 |
| Connecta Corp Milling, Turning, Swiss | Indianapolis, IN | MillingTurningSwiss | - |
| Conroe Machine, LLC Milling, Turning, Laser, Bending, Welding, EDM, Grinding, Finishing · ISO 9001 | Conroe, TX | MillingTurningLaserBendingWeldingEDMGrindingFinishing | ISO 9001 |
| Continental Machining Co Milling, Turning, Welding, EDM | Albuquerque, NM | MillingTurningWeldingEDM | - |
| Contract Machining Milling, Turning, Welding · ISO 9001 | Lexington, KY | MillingTurningWelding | ISO 9001 |
| Conturo Prototyping, LLC Milling, Turning | Pittsburgh, PA | MillingTurning | - |
| Core Shapers, Inc Milling · AS9100, ITAR | Foley, AL | Milling | AS9100, ITAR |
| Cox Machine LLC Milling, Turning, Welding, EDM, Grinding, Finishing · ISO 9001, ITAR | Traverse City, MI | MillingTurningWeldingEDMGrindingFinishing | ISO 9001, ITAR |
| Cox Manufacturing Co Milling, Turning, Swiss, EDM · ISO 9001, ITAR | San Antonio, TX | MillingTurningSwissEDM | ISO 9001, ITAR |
| CP Industries Inc Milling, Welding, Casting | Granger, IN | MillingWeldingCasting | - |
| Creative Custom Products Milling, Welding | Phoenix, AZ | MillingWelding | - |
| CS Tool Engineering, Inc Milling, Welding | Cedar Springs, MI | MillingWelding | - |
| Csi Manufacturing Inc Milling, Turning, Laser, Welding, Stamping, Finishing · ISO 9001 | Westborough, MA | MillingTurningLaserWeldingStampingFinishing | ISO 9001 |
| Cubitek, Inc Milling, Turning, EDM, Grinding · ISO 9001, AS9100 | Brentwood, NY | MillingTurningEDMGrinding | ISO 9001, AS9100 |
| Cumberland Machine Co Milling, Turning, Welding | Nashville, TN | MillingTurningWelding | - |
| Cunningham Machine Co Milling, Turning · ISO 9001, AS9100, ITAR | Chelmsford, MA | MillingTurning | ISO 9001, AS9100, ITAR |
| Curry Precision Machining LLC Milling, Turning | Winchester, CA | MillingTurning | - |
| Custom Engineering Co Milling, Turning, Bending, Welding · ISO 9001, ITAR, NADCAP | Erie, PA | MillingTurningBendingWelding | ISO 9001, ITAR, NADCAP |
| Custom Machine Milling, Turning, Welding, Grinding | Hagerstown, MD | MillingTurningWeldingGrinding | - |
| Custom Machine & Design Inc Milling, Turning, Waterjet, Welding, EDM, Grinding | Lincoln, NE | MillingTurningWaterjetWeldingEDMGrinding | - |
| Custom Machine Inc Milling, Turning, EDM · ISO 9001, AS9100, ITAR, ISO 13485, NADCAP | Woburn, MA | MillingTurningEDM | ISO 9001, AS9100, ITAR, ISO 13485, NADCAP |
| Custom Metal Fabricators Milling, Bending, Laser, Welding | Richmond, VA | MillingBendingLaserWelding | - |
| Custom Metal Works Milling, Bending, Welding | Tulsa, OK | MillingBendingWelding | - |
| Custom Tool & Model Corp Milling, Turning, Laser, Bending, Welding, Stamping, EDM, Grinding · ISO 9001, AS9100 | Frankfort, NY | MillingTurningLaserBendingWeldingStampingEDMGrinding | ISO 9001, AS9100 |
| Custom Tool Inc Milling, Swiss · ISO 9001 | Cookeville, TN | MillingSwiss | ISO 9001 |