| Campbell Engineering Milling, Welding, EDM, Finishing, Assembly · ISO 9001, ITAR | Lake Forest, CA | MillingWeldingEDMFinishingAssembly | ISO 9001, ITAR |
| Heimaster Metal Works Inc Bending, Welding | Lakeside, CA | BendingWelding | - |
| Hi Performance Machine & Metals, Inc Milling, Turning, Waterjet, EDM · ISO 9001 | Lakeside, CA | MillingTurningWaterjetEDM | ISO 9001 |
| Parallax Manufacturing LLC Milling, Turning, Bending, Welding, Stamping, Assembly · NADCAP | Lake Elsinore, CA | MillingTurningBendingWeldingStampingAssembly | NADCAP |
| RBH Aerospace Inc Milling, Turning, Waterjet, Bending | Lakewood, CA | MillingTurningWaterjetBending | - |
| TQ Systems Inc Milling, Turning, EDM, Assembly | Lake Forest, CA | MillingTurningEDMAssembly | - |
| Trio Metal Stamping, Inc Milling, Turning, Laser, Bending, Welding, Stamping, EDM, Grinding · ISO 9001, NADCAP | City Of Industry, CA | MillingTurningLaserBendingWeldingStampingEDMGrinding | ISO 9001, NADCAP |
| Advanced Engineering & EDM, Inc Milling, Turning, Laser, Stamping, EDM, Grinding | Poway, CA | MillingTurningLaserStampingEDMGrinding | - |
| HP Machine & Engineering Inc Milling, Turning, EDM | San Jose, CA | MillingTurningEDM | - |
| Infinity Precision Inc Milling, Turning, Waterjet, Bending, Grinding · ISO 9001, AS9100 | Simi Valley, CA | MillingTurningWaterjetBendingGrinding | ISO 9001, AS9100 |
| Metal Fusion Inc Milling, Turning, Welding, Grinding | Redwood City, CA | MillingTurningWeldingGrinding | - |
| Powers Bros Machine Inc Welding, Grinding | Montebello, CA | WeldingGrinding | - |
| Precision Machining & Fab Milling, Turning, Bending, Laser, Welding, Waterjet · ISO 9001, AS9100, ITAR | Anaheim, CA | MillingTurningBendingLaserWeldingWaterjet | ISO 9001, AS9100, ITAR |
| RC Industries Milling · ISO 9001, AS9100 | Anaheim, CA | Milling | ISO 9001, AS9100 |