| Milner's Anodizing Finishing · NADCAP | Santa Rosa, CA | Finishing | NADCAP |
| Next Tech Manufacturing Inc Milling, Welding, Finishing | Santa Clara, CA | MillingWeldingFinishing | - |
| Omega Precision Milling, Turning · ISO 9001 | Santa Fe Springs, CA | MillingTurning | ISO 9001 |
| Precision Ferrites & Ceramic Milling, Grinding · AS9100 | Huntington Beach, CA | MillingGrinding | AS9100 |
| Prisecter Aerospace and Defense LLC Milling, Turning, Waterjet, Welding, Assembly · AS9100, ITAR, CMMC | Auburn, CA | MillingTurningWaterjetWeldingAssembly | AS9100, ITAR, CMMC |
| Pulse Precision LLC Milling, EDM · ISO 9001 | Santa Ana, CA | MillingEDM | ISO 9001 |
| Radian Thermal Products, Inc Milling, Casting, Finishing · ISO 9001, ITAR | Santa Clara, CA | MillingCastingFinishing | ISO 9001, ITAR |
| Rah Industries Inc Milling, Turning, Laser, Waterjet, Punching, Bending, Welding, Finishing, Assembly · ISO 9001, AS9100, NADCAP | Santa Clarita, CA | MillingTurningLaserWaterjetPunchingBendingWeldingFinishingAssembly | ISO 9001, AS9100, NADCAP |
| Ricaurte Precision Inc Milling, Turning, Swiss, Laser, EDM, Finishing, Assembly · ISO 9001, ITAR | Santa Ana, CA | MillingTurningSwissLaserEDMFinishingAssembly | ISO 9001, ITAR |
| Richards Machining Co Inc Milling, Turning | Santa Clara, CA | MillingTurning | - |
| Robertson Machine Inc Milling, Turning | Santa Clara, CA | MillingTurning | - |
| Scandic Springs, Inc Stamping · ISO 9001 | San Leandro, CA | Stamping | ISO 9001 |
| Scotia Engineering, Inc Milling, Waterjet, Bending, Welding, Stamping, EDM, Grinding, Assembly | Santa Fe Springs, CA | MillingWaterjetBendingWeldingStampingEDMGrindingAssembly | - |
| SOS Steel Co Inc Welding | Santa Clara, CA | Welding | - |
| Swiss Screw Products Inc Milling, Turning, Swiss, Grinding, Assembly · ISO 9001 | Santa Clara, CA | MillingTurningSwissGrindingAssembly | ISO 9001 |
| TM Industries Inc Milling, Welding | Santa Clara, CA | MillingWelding | - |
| Wire Works EDM Inc Milling, Turning, Welding, EDM, Assembly · CMMC | Santa Ana, CA | MillingTurningWeldingEDMAssembly | CMMC |
| Burnet Machining Inc Milling, Turning | Goleta, CA | MillingTurning | - |
| A & D Precision Manufacturing Milling, Turning, Bending, Welding · ISO 9001, AS9100, ITAR | Anaheim, CA | MillingTurningBendingWelding | ISO 9001, AS9100, ITAR |
| A & M Engineering Inc Milling | Irwindale, CA | Milling | - |
| A Precision Machining Corp Milling · AS9100, ITAR, CMMC | Shingle Springs, CA | Milling | AS9100, ITAR, CMMC |
| A&A Machine Milling, Swiss, EDM · AS9100 | Gardena, CA | MillingSwissEDM | AS9100 |
| Above All CNC Inc Milling, Turning · ISO 9001, AS9100, ITAR | Goleta, CA | MillingTurning | ISO 9001, AS9100, ITAR |
| Absolute Precision Machining, Inc. Turning, Welding · ISO 9001, AS9100 | Anaheim, CA | TurningWelding | ISO 9001, AS9100 |
| Advanced Fabrication Technology Laser, Punching, Welding, Finishing, Assembly · ISO 9001 | Hayward, CA | LaserPunchingWeldingFinishingAssembly | ISO 9001 |
| Advantage Metal Products, Inc Milling, Bending, Finishing, Assembly · ITAR | Livermore, CA | MillingBendingFinishingAssembly | ITAR |
| Aero Industries, LLC Milling · ISO 9001 | Buellton, CA | Milling | ISO 9001 |
| Aerospace Manufacturing Inc Welding, Assembly · AS9100 | Canyon Countrt, CA | WeldingAssembly | AS9100 |
| Aerotech Precision Machining, Inc Milling, Turning, Assembly · ISO 9001, AS9100 | Lancaster, CA | MillingTurningAssembly | ISO 9001, AS9100 |
| All-Around Fabrication Inc Milling, Laser, Bending, Welding · ITAR | Sacramento, CA | MillingLaserBendingWelding | ITAR |
| APV Manufacturing Milling, Waterjet, Bending, Welding, Grinding · NADCAP | Buena Park, CA | MillingWaterjetBendingWeldingGrinding | NADCAP |
| Avalon Mfg, Inc Milling · AS9100 | Compton, CA | Milling | AS9100 |
| Azure Microdynamics, Inc Milling, Turning, Swiss, Welding, EDM · ISO 9001, ISO 13485 | Foothill Ranch, CA | MillingTurningSwissWeldingEDM | ISO 9001, ISO 13485 |
| B & D Precision Welding Milling, Turning, Welding, Grinding | Pomona, CA | MillingTurningWeldingGrinding | - |
| Bell Machine Works Milling, Finishing · ISO 9001, ITAR | Gilroy, CA | MillingFinishing | ISO 9001, ITAR |
| Beltim & Associates, LLC Milling, Turning, Swiss, Waterjet, Stamping, Casting, EDM, Finishing · ISO 9001, ITAR, ISO 13485 | Pleasanton, CA | MillingTurningSwissWaterjetStampingCastingEDMFinishing | ISO 9001, ITAR, ISO 13485 |
| Britech Electropolishing Inc Welding, Finishing | Newark, CA | WeldingFinishing | - |
| BS Designs Inc Milling, Turning, Welding | Santee, CA | MillingTurningWelding | - |
| C & S Aerospace, Inc Milling, Turning, EDM | Fullerton, CA | MillingTurningEDM | - |
| C & W Manufacturing Milling, Turning, Welding, Grinding, Finishing · ISO 9001, ITAR, CMMC | Turlock, CA | MillingTurningWeldingGrindingFinishing | ISO 9001, ITAR, CMMC |
| C F W Precision Metal Components Waterjet, Assembly · ISO 9001 | Grover Beach, CA | WaterjetAssembly | ISO 9001 |
| Cal Tech Precision Inc Milling, Turning | Anaheim, CA | MillingTurning | - |
| Calidad, Inc Casting · ISO 9001, AS9100, ITAR | Ontario, CA | Casting | ISO 9001, AS9100, ITAR |
| California Amforge Corp Welding, Forging · ISO 9001, AS9100, ITAR, NADCAP | Azusa, CA | WeldingForging | ISO 9001, AS9100, ITAR, NADCAP |
| Campbell Engineering Milling, Welding, EDM, Finishing, Assembly · ISO 9001, ITAR | Lake Forest, CA | MillingWeldingEDMFinishingAssembly | ISO 9001, ITAR |
| Carney Mfg LLC Milling | Beaumont, CA | Milling | - |
| Coast Metal Cutting Turning | San Jose, CA | Turning | - |
| Computer Integrated Machining Inc Milling, Turning, Waterjet, Welding, Stamping, EDM, Grinding, Assembly · ISO 9001, ITAR | Santee, CA | MillingTurningWaterjetWeldingStampingEDMGrindingAssembly | ISO 9001, ITAR |
| D & H Engineering Inc Milling, EDM · AS9100 | Camarillo, CA | MillingEDM | AS9100 |
| Delta Hi-Tech Milling, Turning, Swiss, Laser, Bending, Welding, EDM, Finishing, Assembly · ISO 9001, AS9100, ITAR, NADCAP, ISO 13485 | Chatsworth, CA | MillingTurningSwissLaserBendingWeldingEDMFinishingAssembly | ISO 9001, AS9100, ITAR, NADCAP, ISO 13485 |