| All-Around Fabrication Inc Milling, Laser, Bending, Welding · ITAR | Sacramento, CA | MillingLaserBendingWelding | ITAR |
| All-In Machining LLC Milling, Turning | Tracy, CA | MillingTurning | - |
| All-Ways Metal Inc Milling, Turning, Laser, Punching, Bending, Welding, Grinding · ISO 9001, ITAR | Gardena, CA | MillingTurningLaserPunchingBendingWeldingGrinding | ISO 9001, ITAR |
| Allied Mechanical Milling, Turning, Bending, Welding, EDM, Grinding, Assembly | Ontario, CA | MillingTurningBendingWeldingEDMGrindingAssembly | - |
| Alloy Metal Products Milling, Turning, EDM, Assembly | Livermore, CA | MillingTurningEDMAssembly | - |
| Alltech Precision Manufacturing Milling, Turning, EDM | Valencia, CA | MillingTurningEDM | - |
| Alpha Precision CNC, LLC Milling, Turning | Fremont, CA | MillingTurning | - |
| American Precision Assembly Assembly · ISO 9001, AS9100 | Huntington Beach, CA | Assembly | ISO 9001, AS9100 |
| Amex Plating Inc Finishing | Santa Clara, CA | Finishing | - |
| AMS Manufacturing Welding, EDM, Finishing, Assembly | San Jose, CA | WeldingEDMFinishingAssembly | - |
| Anaheim Precision Milling, Turning, Bending, Laser, Welding, Waterjet · ISO 9001, AS9100, NADCAP | Orange, CA | MillingTurningBendingLaserWeldingWaterjet | ISO 9001, AS9100, NADCAP |
| Atmosphere Machining LLC Milling, Turning, Waterjet, Welding, Finishing · ITAR | Tehachapi, CA | MillingTurningWaterjetWeldingFinishing | ITAR |
| Avalon Mfg, Inc Milling · AS9100 | Compton, CA | Milling | AS9100 |
| Axis Product Development, Inc Milling · ITAR | Santa Ana, CA | Milling | ITAR |
| Axton Robotics LLC Milling, Turning, Finishing | San Diego, CA | MillingTurningFinishing | - |
| 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 | - |
| B & F Modern Manufacturing, Inc Milling, Turning, Assembly | Santa Ana, CA | MillingTurningAssembly | - |
| Beam on Technology Corporation Laser, Assembly · ITAR | Santa Clara, CA | LaserAssembly | ITAR |
| 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 |
| Benen Manufacturing LLC Milling, Turning, Welding, Finishing, Assembly · ISO 9001, ISO 13485 | San Jose, CA | MillingTurningWeldingFinishingAssembly | ISO 9001, ISO 13485 |
| Beyond Precision, LLC Milling, Turning · ISO 9001, AS9100 | Santa Ana, CA | MillingTurning | ISO 9001, AS9100 |
| Britech Electropolishing Inc Welding, Finishing | Newark, CA | WeldingFinishing | - |
| Burnet Machining Inc Milling, Turning | Goleta, CA | MillingTurning | - |
| Cal Machine & Manufacturing LLC Milling, Turning, Welding, Assembly · ISO 9001, AS9100 | Chino, CA | MillingTurningWeldingAssembly | ISO 9001, AS9100 |
| Calidad, Inc Casting · ISO 9001, AS9100, ITAR | Ontario, CA | Casting | ISO 9001, AS9100, ITAR |
| California Lasers Inc Milling, Laser, Welding, EDM, Grinding | Simi Valley, CA | MillingLaserWeldingEDMGrinding | - |
| CalWest MFG Milling, Turning, Laser, Waterjet, Bending, Welding · ISO 9001, ITAR | Fontana, CA | MillingTurningLaserWaterjetBendingWelding | ISO 9001, ITAR |
| Carney Mfg LLC Milling | Beaumont, CA | Milling | - |
| Cellpoint Systems, Inc Stamping, Assembly | Fremont, CA | StampingAssembly | - |
| Coast Aerospace Manufacturing, Inc Milling, Welding · AS9100, ITAR | Placentia, CA | MillingWelding | AS9100, ITAR |
| Coast Metal Cutting Turning | San Jose, CA | Turning | - |
| Colleen & Herb Enterprises Inc Milling, Turning, Welding | Fremont, CA | MillingTurningWelding | - |
| CPK Manufacturing Milling, Turning, EDM · ISO 9001 | San Jose, CA | MillingTurningEDM | ISO 9001 |
| Cutting Edge Manufacturing Milling, Turning, Assembly · ISO 9001, AS9100 | Newbury Park, CA | MillingTurningAssembly | ISO 9001, AS9100 |
| D & H Engineering Inc Milling, EDM · AS9100 | Camarillo, CA | MillingEDM | AS9100 |
| D-Tek Manufacturing Milling, Turning · ISO 9001, AS9100, ITAR, ISO 13485 | Santa Clara, CA | MillingTurning | ISO 9001, AS9100, ITAR, ISO 13485 |
| Data Electronic Services Finishing · ISO 9001, ITAR | Santa Ana, CA | Finishing | ISO 9001, ITAR |
| Deking Precision Inc Turning, Swiss · ISO 9001, AS9100 | Chatsworth, CA | TurningSwiss | ISO 9001, AS9100 |
| Dinucci Corp Milling, Turning · AS9100 | Concord, CA | MillingTurning | AS9100 |
| Donal Machine Inc Laser, Welding, Finishing · NADCAP | Petaluma, CA | LaserWeldingFinishing | NADCAP |
| DP Products, Inc Milling, Turning, EDM · ISO 9001 | San Jose, CA | MillingTurningEDM | ISO 9001 |
| Eagle Valley Industries, LLC Turning, Waterjet, Bending, Welding | Penn Valley, CA | TurningWaterjetBendingWelding | - |
| Eas Manufacturing Co Milling, Turning, Welding, EDM, Grinding | Camarillo, CA | MillingTurningWeldingEDMGrinding | - |
| Elco Machine Company Milling, Turning, Finishing | San Luis Obispo, CA | MillingTurningFinishing | - |
| Electronic Carbide, Inc Milling, Turning, EDM, Grinding · ITAR | Grass Valley, CA | MillingTurningEDMGrinding | ITAR |
| Element Machine Milling, Turning · ISO 9001, AS9100 | Anaheim, CA | MillingTurning | ISO 9001, AS9100 |
| Embee Processing LLC Welding, Finishing | Santa Ana, CA | WeldingFinishing | - |
| Ems Automotive Milling, Turning, Welding, Grinding · ISO 9001, ITAR | Orange, CA | MillingTurningWeldingGrinding | ISO 9001, ITAR |