| Beyond Precision, LLC Milling, Turning · ISO 9001, AS9100 | Santa Ana, CA | MillingTurning | ISO 9001, AS9100 |
| Bob’s Welding, Machining & Fabrication, Inc. Bending, Welding | Anaheim, CA | BendingWelding | - |
| Braun Co. Engineering LLC Milling, Turning, Swiss, Grinding | Signal Hill, CA | MillingTurningSwissGrinding | - |
| Britech Electropolishing Inc Welding, Finishing | Newark, CA | WeldingFinishing | - |
| BS Designs Inc Milling, Turning, Welding | Santee, CA | MillingTurningWelding | - |
| Bullet Fabrication LLC Milling, Bending, Welding | Gardena, CA | MillingBendingWelding | - |
| C & C Machining, Inc Milling, Turning, EDM, Grinding, Finishing | Hayward, CA | MillingTurningEDMGrindingFinishing | - |
| Cal Machine & Manufacturing LLC Milling, Turning, Welding, Assembly · ISO 9001, AS9100 | Chino, CA | MillingTurningWeldingAssembly | ISO 9001, AS9100 |
| Cal Tech Precision Inc Milling, Turning | Anaheim, CA | MillingTurning | - |
| California Amforge Corp Welding, Forging · ISO 9001, AS9100, ITAR, NADCAP | Azusa, CA | WeldingForging | ISO 9001, AS9100, ITAR, NADCAP |
| California Sheet Metal Bending, Laser, Welding, Waterjet | El Cajon, CA | BendingLaserWeldingWaterjet | - |
| Calrod Engineering, LLC Milling, Turning, Welding · ISO 9001, AS9100, ITAR | Costa Mesa, CA | MillingTurningWelding | ISO 9001, AS9100, ITAR |
| Carney Mfg LLC Milling | Beaumont, CA | Milling | - |
| Casco Machining Inc. Milling, Turning, Welding · ISO 9001 | San Jose, CA | MillingTurningWelding | ISO 9001 |
| Cellpoint Systems, Inc Stamping, Assembly | Fremont, CA | StampingAssembly | - |
| Clint Precision Manufacturing Milling, Turning, Welding, Waterjet · ISO 9001 | San Diego, CA | MillingTurningWeldingWaterjet | ISO 9001 |
| CNC Machining & Engineering Inc Milling, Turning, Swiss | Ontario, CA | MillingTurningSwiss | - |
| Colleen & Herb Enterprises Inc Milling, Turning, Welding | Fremont, CA | MillingTurningWelding | - |
| Compucraft Industries, Inc Waterjet, Punching, Bending, Welding, EDM, Finishing, Assembly · AS9100, NADCAP | Santee, CA | WaterjetPunchingBendingWeldingEDMFinishingAssembly | AS9100, NADCAP |
| Computer Assisted Manufacturing Technology LLC Milling, Assembly · ISO 9001 | Irvine, CA | MillingAssembly | ISO 9001 |
| Computer Integrated Machining Inc Milling, Turning, Waterjet, Welding, Stamping, EDM, Grinding, Assembly · ISO 9001, ITAR | Santee, CA | MillingTurningWaterjetWeldingStampingEDMGrindingAssembly | ISO 9001, ITAR |
| Cortec Precision Sheetmetal Milling, Turning, Bending, Laser, Welding | San Jose, CA | MillingTurningBendingLaserWelding | - |
| Crater Industries LLC Milling, Turning, EDM, Grinding, Assembly | Santa Clarita, CA | MillingTurningEDMGrindingAssembly | - |
| Curry Precision Machining LLC Milling, Turning | Winchester, CA | MillingTurning | - |
| Cutting Edge Manufacturing Milling, Turning, Assembly · ISO 9001, AS9100 | Newbury Park, CA | MillingTurningAssembly | ISO 9001, AS9100 |
| D-Tek Manufacturing Milling, Turning · ISO 9001, AS9100, ITAR, ISO 13485 | Santa Clara, CA | MillingTurning | ISO 9001, AS9100, ITAR, ISO 13485 |
| Defense & Aerospace Manufacturing LLC Welding, Grinding, Finishing, Assembly | Rancho Cordova, CA | WeldingGrindingFinishingAssembly | - |
| Deking Precision Inc Turning, Swiss · ISO 9001, AS9100 | Chatsworth, CA | TurningSwiss | ISO 9001, AS9100 |
| Delta Machine Company, LLC Milling, Turning, Welding, Grinding | Harbor City, CA | MillingTurningWeldingGrinding | - |
| deMel Fabrication Bending, Laser, Welding | Anaheim, CA | BendingLaserWelding | - |
| DG Engineering Corp Milling, Turning | Sylmar, CA | MillingTurning | - |
| Dinucci Corp Milling, Turning · AS9100 | Concord, CA | MillingTurning | AS9100 |
| Dix Metals Milling, Waterjet, Welding, Stamping, Grinding | Huntington Beach, CA | MillingWaterjetWeldingStampingGrinding | - |
| DT Precision, LLC Milling, Turning, Swiss · ISO 9001, AS9100, ITAR, ISO 13485 | San Jose, CA | MillingTurningSwiss | ISO 9001, AS9100, ITAR, ISO 13485 |
| E2e, Mfg LLC Milling, Casting, EDM | Fremont, CA | MillingCastingEDM | - |
| Ea Machining Inc Milling, Turning · AS9100 | Santa Clara, CA | MillingTurning | AS9100 |
| Eagle Valley Industries, LLC Turning, Waterjet, Bending, Welding | Penn Valley, CA | TurningWaterjetBendingWelding | - |
| Eas Manufacturing Co Milling, Turning, Welding, EDM, Grinding | Camarillo, CA | MillingTurningWeldingEDMGrinding | - |
| Ejays Machine Co Inc Milling, Bending, Assembly · ISO 9001, AS9100 | Fullerton, CA | MillingBendingAssembly | ISO 9001, AS9100 |
| Element Machine Milling, Turning · ISO 9001, AS9100 | Anaheim, CA | MillingTurning | ISO 9001, AS9100 |
| Elliptical Sheet Metal Mfg LLC Milling, Punching, Bending, Welding | Huntington Beach, CA | MillingPunchingBendingWelding | - |
| Embee Processing LLC Welding, Finishing | Santa Ana, CA | WeldingFinishing | - |
| Englebrecht Precision Machining Milling, Turning | Hesperia, CA | MillingTurning | - |
| Etogen Precision Milling, Turning, Welding · ISO 9001, AS9100, ITAR | San Diego, CA | MillingTurningWelding | ISO 9001, AS9100, ITAR |
| Euro Machining Enterprise Inc Milling, Turning, Welding, Grinding, Assembly · ISO 9001 | Santa Clara, CA | MillingTurningWeldingGrindingAssembly | ISO 9001 |
| Euro Precision, Inc Milling, Turning · ISO 9001, ITAR | Anaheim, CA | MillingTurning | ISO 9001, ITAR |
| Evert Hancock Inc Milling, Laser, Waterjet, Punching, Bending, Welding · ISO 9001, AS9100, NADCAP | Anaheim, CA | MillingLaserWaterjetPunchingBendingWelding | ISO 9001, AS9100, NADCAP |
| Excel Machining Milling, Turning, Bending, Welding, Waterjet · ISO 9001 | Santa Clara, CA | MillingTurningBendingWeldingWaterjet | ISO 9001 |
| Ez Engineering LLC Milling, Turning · AS9100 | Orange, CA | MillingTurning | AS9100 |
| Farrar Aerospace LLC Milling, Turning · ISO 9001, ITAR | Ontario, CA | MillingTurning | ISO 9001, ITAR |