| Hilltop Technology Laboratory Inc Milling | Irvine, CA | Milling | - |
| Hitech Metalfab Inc Bending, Welding · ISO 9001 | Santa Clara, CA | BendingWelding | ISO 9001 |
| HMF Corporation Bending, Laser, Welding | Anaheim, CA | BendingLaserWelding | - |
| Hubbell Machine Co Inc Milling, Turning, Finishing · ISO 9001, AS9100 | Paso Robles, CA | MillingTurningFinishing | ISO 9001, AS9100 |
| Hyperformance Products Inc Milling, Turning, Punching, Bending, Welding | Huntington Beach, CA | MillingTurningPunchingBendingWelding | - |
| J & T Manufacturing & Engineering Milling, Turning | San Diego, CA | MillingTurning | - |
| Jarvis Manufacturing, Inc Milling, Turning, EDM, Assembly · ISO 9001, ITAR | San Jose, CA | MillingTurningEDMAssembly | ISO 9001, ITAR |
| Jims Machining Milling, Turning · ISO 9001 | Camarillo, CA | MillingTurning | ISO 9001 |
| JP Metal Fabrication, Inc. Milling, Bending, Laser, Welding | Santa Clara, CA | MillingBendingLaserWelding | - |
| JWP Manufacturing Milling, Swiss, EDM | Santa Clara, CA | MillingSwissEDM | - |
| Kap Manufacturing, Inc Milling · ISO 9001 | San Dimas, CA | Milling | ISO 9001 |
| KB Sheetmetal Fabrication, Inc Turning, Bending, Welding, Finishing · ISO 9001 | Fountain Valley, CA | TurningBendingWeldingFinishing | ISO 9001 |
| Marx Digital Manufacturing Inc Milling, Turning, Welding, Assembly | Santa Clara, CA | MillingTurningWeldingAssembly | - |
| Maxpol Precision Machining Milling, Turning | Morgan Hill, CA | MillingTurning | - |
| Metalid Manufacturing Inc Milling · ISO 9001 | Pacoima, CA | Milling | ISO 9001 |
| Metri Tech Engineering Inc Milling, EDM, Assembly · ISO 9001, AS9100 | Huntington Beach, CA | MillingEDMAssembly | ISO 9001, AS9100 |
| Micro-Tec, Inc Milling, Turning, Welding, EDM, Finishing · ISO 9001, AS9100 | Chatsworth, CA | MillingTurningWeldingEDMFinishing | ISO 9001, AS9100 |
| Microform Precision LLC Turning, Bending, Laser, Welding, Waterjet | Sacramento, CA | TurningBendingLaserWeldingWaterjet | - |
| Millennium Metalcraft, Inc Milling, Laser, Bending, Welding, Finishing, Assembly · ISO 9001 | Fremont, CA | MillingLaserBendingWeldingFinishingAssembly | ISO 9001 |
| Millipart, Inc Milling, Turning · ISO 9001, AS9100 | Glendora, CA | MillingTurning | ISO 9001, AS9100 |
| Modern Custom Fabrication Welding | Fresno, CA | Welding | - |
| Opti-Forms Inc Stamping, EDM, Finishing · ISO 9001, ITAR | Temecula, CA | StampingEDMFinishing | ISO 9001, ITAR |
| Pacific Maritime Industries Corp Milling, Turning, Laser, Waterjet, Punching, Bending, Welding · ISO 9001 | San Diego, CA | MillingTurningLaserWaterjetPunchingBendingWelding | ISO 9001 |
| Pacific Precision Machine Inc Milling, Turning, Welding | Sonora, CA | MillingTurningWelding | - |
| Peacock Tool & Engineering Milling, Turning · AS9100, ITAR, CMMC | Spring Valley, CA | MillingTurning | AS9100, ITAR, CMMC |
| Powers Bros Machine Inc Welding, Grinding | Montebello, CA | WeldingGrinding | - |
| Precision Ferrites & Ceramic Milling, Grinding · AS9100 | Huntington Beach, CA | MillingGrinding | AS9100 |
| Price Products Inc Milling, Swiss · ISO 9001, ITAR | Escondido, CA | MillingSwiss | ISO 9001, ITAR |
| Prisecter Aerospace and Defense LLC Milling, Turning, Waterjet, Welding, Assembly · AS9100, ITAR, CMMC | Auburn, CA | MillingTurningWaterjetWeldingAssembly | AS9100, ITAR, CMMC |
| Pro-Tek Manufacturing Inc Bending, Welding | Livermore, CA | BendingWelding | - |
| PTG Precision LLC Milling, Turning, Swiss, Welding, Grinding, Assembly · ISO 9001, AS9100, ITAR, CMMC | Gardena, CA | MillingTurningSwissWeldingGrindingAssembly | ISO 9001, AS9100, ITAR, CMMC |
| Qualitask Inc Milling, Turning, Swiss, Welding, EDM, Grinding, Finishing, Assembly · ISO 9001, AS9100 | Anaheim, CA | MillingTurningSwissWeldingEDMGrindingFinishingAssembly | ISO 9001, AS9100 |
| Quality Machining & Design Inc Milling, EDM · ISO 9001 | San Jose, CA | MillingEDM | ISO 9001 |
| Ram Aerospace Inc Milling, Turning, Laser, Waterjet, EDM, Grinding, Assembly · AS9100, ITAR | Brea, CA | MillingTurningLaserWaterjetEDMGrindingAssembly | AS9100, ITAR |
| RBH Aerospace Inc Milling, Turning, Waterjet, Bending | Lakewood, CA | MillingTurningWaterjetBending | - |
| San Diego Precision Machining Inc Milling, Turning, Welding, EDM · ISO 9001, AS9100 | San Diego, CA | MillingTurningWeldingEDM | ISO 9001, AS9100 |
| Scotia Engineering, Inc Milling, Waterjet, Bending, Welding, Stamping, EDM, Grinding, Assembly | Santa Fe Springs, CA | MillingWaterjetBendingWeldingStampingEDMGrindingAssembly | - |
| Si Aerospace Inc Milling · ISO 9001, AS9100, ITAR | Van Nuys, CA | Milling | ISO 9001, AS9100, ITAR |
| SOS Steel Co Inc Welding | Santa Clara, CA | Welding | - |
| SP Manufacturing Inc Milling, Turning, Welding, Finishing · ISO 9001, AS9100 | Livermore, CA | MillingTurningWeldingFinishing | ISO 9001, AS9100 |
| Stigtec Manufacturing Milling, Welding, EDM, Grinding, Finishing, Assembly | San Marcos, CA | MillingWeldingEDMGrindingFinishingAssembly | - |
| Superior Precision Machining LLC Milling · ISO 9001, ITAR, ISO 13485 | Fremont, CA | Milling | ISO 9001, ITAR, ISO 13485 |
| Surfacemode, Inc Milling · ISO 9001, AS9100, ITAR | San Diego, CA | Milling | ISO 9001, AS9100, ITAR |
| Swiss Screw Products Inc Milling, Turning, Swiss, Grinding, Assembly · ISO 9001 | Santa Clara, CA | MillingTurningSwissGrindingAssembly | ISO 9001 |
| TDC Manufacturing Inc Milling, Turning, Laser | Redlands, CA | MillingTurningLaser | - |
| TJ Aerospace Inc Milling, Assembly | Garden Grove, CA | MillingAssembly | - |
| Tough Cut Manufacturing Milling, Turning · AS9100 | Anaheim, CA | MillingTurning | AS9100 |
| Tri Fab Associates, Inc Milling, Turning, Laser, Punching, Welding, Stamping, Grinding, Finishing, Assembly · ISO 9001, AS9100, ITAR, CMMC | Fremont, CA | MillingTurningLaserPunchingWeldingStampingGrindingFinishingAssembly | ISO 9001, AS9100, ITAR, CMMC |
| Tri Models Inc Milling, Turning, EDM, Finishing, Assembly | Huntington Beach, CA | MillingTurningEDMFinishingAssembly | - |
| Trussworks International Inc Bending, Welding · ISO 9001 | Pomona, CA | BendingWelding | ISO 9001 |