| Genfor Precision Components Limited Milling, Turning, Swiss | Chanhassen, MN | MillingTurningSwiss | - |
| Giuliante Machine Tool Inc Milling, Turning, EDM, Grinding, Finishing · ISO 9001, AS9100 | Peekskill, NY | MillingTurningEDMGrindingFinishing | ISO 9001, AS9100 |
| Grain Belt Supply Company, Inc Turning, Laser, Waterjet, Bending, Welding, Grinding, Finishing, Assembly | Salina, KS | TurningLaserWaterjetBendingWeldingGrindingFinishingAssembly | - |
| H & H Machine Shop of Akron Inc Milling, Turning, Welding, Grinding | Akron, OH | MillingTurningWeldingGrinding | - |
| Harvey Brothers Inc Bending, Welding | Cincinnati, OH | BendingWelding | - |
| Hastreiter Industries Corp Milling, Turning, Laser, Bending, Welding, Grinding, Finishing · ISO 9001, ITAR | Marshfield, WI | MillingTurningLaserBendingWeldingGrindingFinishing | ISO 9001, ITAR |
| Heighten America, Inc Milling, Turning, Welding, Assembly · ISO 9001 | Oakdale, CA | MillingTurningWeldingAssembly | ISO 9001 |
| HG Metals Bending, Welding | Indianapolis, IN | BendingWelding | - |
| Instrument Development Corp Milling, Turning, EDM | Mukwonago, WI | MillingTurningEDM | - |
| Ipanel Systems Inc Milling | Santa Clarita, CA | Milling | - |
| Irwin Automation Inc Milling, Turning, Welding, EDM, Grinding | Greensburg, PA | MillingTurningWeldingEDMGrinding | - |
| ISCO Manufacturing Solutions Milling, Turning, Waterjet, Bending, Welding, Grinding · ISO 9001, AS9100 | Bend, OR | MillingTurningWaterjetBendingWeldingGrinding | ISO 9001, AS9100 |
| J & L Precision Manufacturing LLC Bending, Welding, Stamping, Finishing, Assembly · ISO 9001 | Brooklyn Heights, OH | BendingWeldingStampingFinishingAssembly | ISO 9001 |
| J.B. Anderson & Son, Inc Milling, Turning, Welding, Assembly | Irwin, PA | MillingTurningWeldingAssembly | - |
| J&J Machine Milling, EDM | Appleton, WI | MillingEDM | - |
| JC Machine, Inc Milling, Turning, Swiss, Laser, Bending, Welding | Lakeland, FL | MillingTurningSwissLaserBendingWelding | - |
| JC Tool & Die, LLC Milling, Turning, Stamping, EDM, Grinding, Assembly · ISO 9001, ITAR | Hull, GA | MillingTurningStampingEDMGrindingAssembly | ISO 9001, ITAR |
| Jeb Modern Machines, Limited Turning, EDM | Republic, OH | TurningEDM | - |
| Jergens Inc Milling, Welding · ISO 9001, AS9100 | Cleveland, OH | MillingWelding | ISO 9001, AS9100 |
| Jet Machine & Mfg Milling, Welding | Hamilton, OH | MillingWelding | - |
| Jet Machine Works, Inc Milling, Turning | Houston, TX | MillingTurning | - |
| Jetfab LLC Milling, Turning, Laser, Waterjet, Punching, Bending, Welding | Lowell, MA | MillingTurningLaserWaterjetPunchingBendingWelding | - |
| JMS Machine, Inc Milling, Turning, EDM, Grinding | Columbia City, IN | MillingTurningEDMGrinding | - |
| Johnson Manufacturing Milling, Turning, Grinding · AS9100 | Huntington Beach, CA | MillingTurningGrinding | AS9100 |
| JP Metal Fabrication, Inc. Milling, Bending, Laser, Welding | Santa Clara, CA | MillingBendingLaserWelding | - |
| K & H Industries, LLC Stamping · ISO 9001 | Cincinnati, OH | Stamping | ISO 9001 |
| K&M Milling, Turning, Laser, Welding, Assembly · ISO 9001 | Cassopolis, MI | MillingTurningLaserWeldingAssembly | ISO 9001 |
| Kadon Precision Machining Turning · ISO 9001 | Rockford, IL | Turning | ISO 9001 |
| Kalco Machine & Manufacturing Co Welding, Assembly · ISO 9001 | Wichita Falls, TX | WeldingAssembly | ISO 9001 |
| Kam Tool & Die Milling, Turning, EDM, Grinding · ISO 9001 | Zebulon, NC | MillingTurningEDMGrinding | ISO 9001 |
| Kasper Industries, Inc Milling, Turning | Gaylord, MI | MillingTurning | - |
| Kennebec Technologies Milling, Grinding, Assembly | Augusta, ME | MillingGrindingAssembly | - |
| Kihm Metal Technologies Laser, Welding | Brazil, IN | LaserWelding | - |
| La Machine Shop, Inc. Milling, Turning, Bending · ISO 9001, AS9100 | Ham Lake, MN | MillingTurningBending | ISO 9001, AS9100 |
| Lai International Inc Milling, Laser, Waterjet, Welding, Metal AM, EDM, Finishing · NADCAP | Westminster, MD | MillingLaserWaterjetWeldingMetal AMEDMFinishing | NADCAP |
| Langdon Inc Welding | Cincinnati, OH | Welding | - |
| Lathrom Manufacturing Inc Milling, Turning, Bending, Grinding · ISO 9001, ITAR | Wichita, KS | MillingTurningBendingGrinding | ISO 9001, ITAR |
| Lawson Precision Machining, Inc Milling, Turning, Welding, Grinding · ISO 9001 | Bucyrus, OH | MillingTurningWeldingGrinding | ISO 9001 |
| Laystrom Manufacturing Company Bending, Laser, Welding | Chicago, IL | BendingLaserWelding | - |
| Legacy Industries Laser, Welding, Stamping · ITAR | Auburn Hills, MI | LaserWeldingStamping | ITAR |
| Lemke Industrial Machine LLC Welding, Grinding | Marathon, WI | WeldingGrinding | - |
| Lewis Precision & CNC Inc Milling, Turning, Bending, Welding, Grinding, Finishing · ISO 9001, AS9100 | Theodore, AL | MillingTurningBendingWeldingGrindingFinishing | ISO 9001, AS9100 |
| LG Metalworks LLC Milling, Turning, Laser, Waterjet, Welding, EDM, Finishing | Bloomington, IN | MillingTurningLaserWaterjetWeldingEDMFinishing | - |
| Lindor Tool, Inc Milling, Turning, Welding, Casting, Grinding | Saint Croix Falls, WI | MillingTurningWeldingCastingGrinding | - |
| Linear Machining Technology LLC Milling, Turning, EDM, Grinding, Finishing · ISO 9001 | Irwin, PA | MillingTurningEDMGrindingFinishing | ISO 9001 |
| Luke Manufacturing Co Casting, Finishing | Wadsworth, OH | CastingFinishing | - |
| LV Swiss Inc Milling, Turning, Swiss, Grinding, Finishing · ISO 9001, AS9100, ITAR, ISO 13485 | La Verkin, UT | MillingTurningSwissGrindingFinishing | ISO 9001, AS9100, ITAR, ISO 13485 |
| M 7 Technologies Bending, Welding · ISO 9001 | Youngstown, OH | BendingWelding | ISO 9001 |
| M-1 Tool Works, Inc Milling, Turning, EDM, Grinding, Finishing, Assembly · ISO 9001, AS9100 | Mchenry, IL | MillingTurningEDMGrindingFinishingAssembly | ISO 9001, AS9100 |
| Machine Shop LLC EDM, Assembly | East Hardwick, VT | EDMAssembly | - |