| 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 | - |
| Delta One Manufacturing LLC Milling, Turning, Laser, Welding, Finishing, Assembly | San Jose, CA | MillingTurningLaserWeldingFinishingAssembly | - |
| Dinucci Corp Milling, Turning · AS9100 | Concord, CA | MillingTurning | AS9100 |
| DP Machining Inc Milling, Turning, Swiss, Stamping, Finishing | La Verne, CA | MillingTurningSwissStampingFinishing | - |
| DT Precision, LLC Milling, Turning, Swiss · ISO 9001, AS9100, ITAR, ISO 13485 | San Jose, CA | MillingTurningSwiss | ISO 9001, AS9100, ITAR, ISO 13485 |
| Dynamic Loop Inc Milling, Turning, Laser, Waterjet, Finishing | Camarillo, CA | MillingTurningLaserWaterjetFinishing | - |
| Dynamic Marine Machining Welding | Spring Valley, CA | Welding | - |
| Ea Machining Inc Milling, Turning · AS9100 | Santa Clara, CA | MillingTurning | AS9100 |
| Eastwood Machine, LLC Milling, Turning, Laser, Waterjet, Welding, EDM, Grinding, Finishing, Assembly | Santee, CA | MillingTurningLaserWaterjetWeldingEDMGrindingFinishingAssembly | - |
| Ejays Machine Co Inc Milling, Bending, Assembly · ISO 9001, AS9100 | Fullerton, CA | MillingBendingAssembly | ISO 9001, AS9100 |
| 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 |
| 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 |
| Exact CNC Industries Inc Milling, Turning, Swiss, Laser · ISO 9001, AS9100, ITAR | Chatsworth, CA | MillingTurningSwissLaser | ISO 9001, AS9100, ITAR |
| Excel Machining Milling, Turning, Bending, Welding, Waterjet · ISO 9001 | Santa Clara, CA | MillingTurningBendingWeldingWaterjet | ISO 9001 |
| Expedite Precision Works Inc Milling, Turning, Swiss, Welding, EDM, Finishing · ISO 9001, AS9100, ITAR, ISO 13485 | San Jose, CA | MillingTurningSwissWeldingEDMFinishing | ISO 9001, AS9100, ITAR, ISO 13485 |
| Express Metal Aerospace Inc Punching, Bending · ISO 9001 | Santa Ana, CA | PunchingBending | ISO 9001 |
| Ez Engineering LLC Milling, Turning · AS9100 | Orange, CA | MillingTurning | AS9100 |
| FandJ Precision Milling, Turning, Finishing · ISO 9001, AS9100, ITAR | Gilroy, CA | MillingTurningFinishing | ISO 9001, AS9100, ITAR |
| Farrell Brothers Holding Corp Milling, Turning, Swiss · ISO 9001, ISO 13485 | Anaheim, CA | MillingTurningSwiss | ISO 9001, ISO 13485 |
| Feral Productions LLC Milling, Turning, Welding, Grinding, Finishing, Assembly | Tracy, CA | MillingTurningWeldingGrindingFinishingAssembly | - |
| Five Star Enterprises Milling, Laser, Waterjet, Welding, Stamping, Metal AM, EDM, Finishing | San Marcos, CA | MillingLaserWaterjetWeldingStampingMetal AMEDMFinishing | - |
| Forza Engineering Group Corp Milling, Turning | Laguna Niguel, CA | MillingTurning | - |
| Franklin’s Industries Milling, Turning, Waterjet, Welding, EDM · ISO 9001, AS9100 | Poway, CA | MillingTurningWaterjetWeldingEDM | ISO 9001, AS9100 |
| Futuristics Machine, Inc. Welding · ISO 9001 | San Diego, CA | Welding | ISO 9001 |
| GC Machining, Inc. Milling, Turning · ISO 9001, AS9100, ITAR | Stockton, CA | MillingTurning | ISO 9001, AS9100, ITAR |
| Gemini Manufacturing & Engineering Inc Milling, Laser, Punching, Welding, Finishing · ISO 9001 | Anaheim, CA | MillingLaserPunchingWeldingFinishing | ISO 9001 |
| General Foundry Service Corp Casting, Finishing · ISO 9001, ITAR | San Leandro, CA | CastingFinishing | ISO 9001, ITAR |
| General Grinding & Mfg Co LLC Milling, Turning, Welding, Grinding, Finishing · ISO 9001, AS9100 | La Mirada, CA | MillingTurningWeldingGrindingFinishing | ISO 9001, AS9100 |
| General Research & Manufacturing Milling, Turning · ISO 9001, AS9100, ITAR | Torrance, CA | MillingTurning | ISO 9001, AS9100, ITAR |
| Green's Metal Cut-Off Corp Turning, Swiss | Santa Fe Springs, CA | TurningSwiss | - |
| Group Manufacturing Services Inc Milling, Turning, Laser, Punching, Bending, Welding, Assembly · ISO 9001 | San Jose, CA | MillingTurningLaserPunchingBendingWeldingAssembly | ISO 9001 |
| Haig Precision Manufacturing Corp Milling, Turning, Laser, Punching, Bending, Welding, Stamping, EDM, Grinding, Finishing, Assembly | San Jose, CA | MillingTurningLaserPunchingBendingWeldingStampingEDMGrindingFinishingAssembly | - |
| Halcyon Manufacturing Inc Milling, Turning, Bending, Welding, EDM, Finishing, Assembly · ITAR | San Jose, CA | MillingTurningBendingWeldingEDMFinishingAssembly | ITAR |
| Hansens Welding Inc Waterjet, Welding | Gardena, CA | WaterjetWelding | - |
| Harcon Precision Metals, Inc Milling, Turning, Laser, Waterjet, Punching, Bending, Welding, Finishing | San Diego, CA | MillingTurningLaserWaterjetPunchingBendingWeldingFinishing | - |
| Hasten Applied CNC LLC Milling, Turning, Swiss, Laser, Bending, Welding, Stamping, EDM, Finishing · ISO 9001, ITAR | Riverside, CA | MillingTurningSwissLaserBendingWeldingStampingEDMFinishing | ISO 9001, ITAR |
| Helical Machining, Inc Milling, Turning, Welding, EDM, Grinding, Finishing, Assembly | Sun Valley, CA | MillingTurningWeldingEDMGrindingFinishingAssembly | - |
| Henry's Metal Polishing, Inc Turning, Bending, Welding, Grinding, Finishing · ISO 9001 | S El Monte, CA | TurningBendingWeldingGrindingFinishing | ISO 9001 |
| Hi Performance Machine & Metals, Inc Milling, Turning, Waterjet, EDM · ISO 9001 | Lakeside, CA | MillingTurningWaterjetEDM | ISO 9001 |
| Hi-Tech Turning Company Turning | Anaheim, CA | Turning | - |
| High Speed CNC Milling, Turning · ISO 9001, AS9100 | Santa Clara, CA | MillingTurning | ISO 9001, AS9100 |
| HM Quality Machining Inc Milling, Turning, Laser, Waterjet, Grinding | Ontario, CA | MillingTurningLaserWaterjetGrinding | - |
| HNDO Precision Milling, Laser, Finishing | Santa Rosa, CA | MillingLaserFinishing | - |
| Hogin Machine, Inc Milling, Turning, Swiss, Waterjet, Bending, Welding | Santa Ana, CA | MillingTurningSwissWaterjetBendingWelding | - |