| K & K Inc Milling, Casting | Elkhart, IN | MillingCasting | - |
| Kammerer Dynamics Inc Laser, Bending, Welding, Casting, Finishing, Assembly | Kendallville, IN | LaserBendingWeldingCastingFinishingAssembly | - |
| Kimura Foundry America, Inc Casting, Metal AM | Shelbyville, IN | CastingMetal AM | - |
| Kosmo Machine Inc Milling, Turning, Welding, Casting, EDM | Sandston, VA | MillingTurningWeldingCastingEDM | - |
| KP Manufacturing Milling, Casting, Finishing, Assembly | Spencer, IA | MillingCastingFinishingAssembly | - |
| Kris Dee and Associates, Inc Milling, Casting · ISO 9001, AS9100, ITAR | South Elgin, IL | MillingCasting | ISO 9001, AS9100, ITAR |
| Lamjen Inc Milling, Turning, Welding, Stamping, Casting · ISO 9001 | Erie, PA | MillingTurningWeldingStampingCasting | ISO 9001 |
| Le Sueur, Incorporated Welding, Casting · ISO 9001 | Le Sueur, MN | WeldingCasting | ISO 9001 |
| Lean Industrial LLC Milling, Casting, Grinding · ISO 9001 | Eugene, OR | MillingCastingGrinding | ISO 9001 |
| Leanwerks, LLC Milling, Turning, Welding, Casting, Grinding, Assembly · ISO 9001, AS9100, ITAR, CMMC | Ogden, UT | MillingTurningWeldingCastingGrindingAssembly | ISO 9001, AS9100, ITAR, CMMC |
| Liberty Cast Products Casting · ISO 9001, AS9100 | Sterling Heights, MI | Casting | ISO 9001, AS9100 |
| Lindor Tool, Inc Milling, Turning, Welding, Casting, Grinding | Saint Croix Falls, WI | MillingTurningWeldingCastingGrinding | - |
| Lomar Machine & Tool Co Milling, Turning, Laser, Bending, Welding, Casting, EDM, Grinding, Finishing · ISO 9001 | Horton, MI | MillingTurningLaserBendingWeldingCastingEDMGrindingFinishing | ISO 9001 |
| Luke Manufacturing Co Casting, Finishing | Wadsworth, OH | CastingFinishing | - |
| Mach Machine Inc Turning, Welding, Stamping, Casting, EDM, Assembly · ISO 9001, ITAR | Hudson, MA | TurningWeldingStampingCastingEDMAssembly | ISO 9001, ITAR |
| Machining Concepts Inc Milling, Turning, Casting · AS9100, ISO 13485 | Erie, PA | MillingTurningCasting | AS9100, ISO 13485 |
| Majestic Metals by Fathom Manufacturing Milling, Turning, Bending, Laser, Welding, Waterjet, EDM, Casting, Metal AM · ISO 9001, AS9100, ITAR, ISO 13485 | Denver, CO | MillingTurningBendingLaserWeldingWaterjetEDMCastingMetal AM | ISO 9001, AS9100, ITAR, ISO 13485 |
| Manufacturing Standard, LLC Milling, Turning, Swiss, Stamping, Casting · ISO 9001, AS9100, IATF 16949 | Poway, CA | MillingTurningSwissStampingCasting | ISO 9001, AS9100, IATF 16949 |
| Master Machine, Inc Milling, Turning, Bending, Casting · ISO 9001 | Minneapolis, MN | MillingTurningBendingCasting | ISO 9001 |
| Maumee Pattern Co Milling, Turning, Casting, EDM · ITAR, CMMC | Toledo, OH | MillingTurningCastingEDM | ITAR, CMMC |
| Max3, LLC Turning, Welding, Casting, EDM | Benton Harbor, MI | TurningWeldingCastingEDM | - |
| Meridian Industrial Group, LLC Milling, Turning, Welding, Casting · ISO 9001, AS9100 | Holyoke, MA | MillingTurningWeldingCasting | ISO 9001, AS9100 |
| Metaltek International Corp Milling, Welding, Casting, Metal AM · NADCAP | Waukesha, WI | MillingWeldingCastingMetal AM | NADCAP |
| Micro-Matics Inc Milling, Turning, Swiss, Casting, EDM, Grinding, Assembly | Fridley, MN | MillingTurningSwissCastingEDMGrindingAssembly | - |
| Mid America Steel Inc Milling, Bending, Welding, Casting | Fargo, ND | MillingBendingWeldingCasting | - |
| Midwest Precision LLC Milling, Turning, Casting, EDM, Grinding, Assembly · ISO 9001, ITAR | Eastlake, OH | MillingTurningCastingEDMGrindingAssembly | ISO 9001, ITAR |
| Mirror Finish Polishing Welding, Casting, Grinding | Kearney, MO | WeldingCastingGrinding | - |
| Modern Forge Indiana LLC Turning, Welding, Casting, Forging, Assembly · ISO 9001, AS9100, NADCAP | Merrillville, IN | TurningWeldingCastingForgingAssembly | ISO 9001, AS9100, NADCAP |
| Morgan Bronze Products, Inc Turning, Welding, Casting · ISO 9001 | Lake Zurich, IL | TurningWeldingCasting | ISO 9001 |
| MP Components Casting · ISO 9001 | Byron Center, MI | Casting | ISO 9001 |
| Non-Ferrous Casting Company Casting | Dayton, OH | Casting | - |
| Northern Gear, LLC Casting, Finishing | Muskego, WI | CastingFinishing | - |
| Northfield Manufacturing, Inc Welding, Casting | Westland, MI | WeldingCasting | - |
| Nuclear Lead Co, Inc Welding, Casting | Oak Ridge, TN | WeldingCasting | - |
| Ofallon Casting LLC Casting, EDM | O Fallon, MO | CastingEDM | - |
| Oil City Iron Works, Inc Milling, Casting · ISO 9001 | Corsicana, TX | MillingCasting | ISO 9001 |
| Olympus Foundry Welding, Casting · AS9100, NADCAP | Millcreek, UT | WeldingCasting | AS9100, NADCAP |
| Omega Tool & Machine Casting · ISO 9001 | Battle Creek, MI | Casting | ISO 9001 |
| OMS Precision Machining Milling, Turning, Swiss, Casting, Grinding, Finishing · ISO 9001, ITAR | Oshkosh, WI | MillingTurningSwissCastingGrindingFinishing | ISO 9001, ITAR |
| Onamac Industries, Inc Milling, Turning, Casting, Grinding · ISO 9001, AS9100 | Everett, WA | MillingTurningCastingGrinding | ISO 9001, AS9100 |
| Owens Industries, Inc. Milling, Turning, Welding, EDM, Casting, Metal AM · ISO 9001, AS9100 | Oak Creek, WI | MillingTurningWeldingEDMCastingMetal AM | ISO 9001, AS9100 |
| Package One Industries, LLC Milling, Swiss, Waterjet, Bending, Welding, Stamping, Casting, Finishing, Assembly · ISO 9001, ITAR, NADCAP | Schenectady, NY | MillingSwissWaterjetBendingWeldingStampingCastingFinishingAssembly | ISO 9001, ITAR, NADCAP |
| Paragon D & E Milling, Bending, Casting · ISO 9001, AS9100, ITAR, CMMC | Grand Rapids, MI | MillingBendingCasting | ISO 9001, AS9100, ITAR, CMMC |
| Pioneer Products, Inc Milling, Turning, Casting, Grinding, Finishing, Assembly | Racine, WI | MillingTurningCastingGrindingFinishingAssembly | - |
| Pme of Ohio, Inc Welding, Casting, Grinding | Minden, NV | WeldingCastingGrinding | - |
| Polyhistor International, Inc. Bending, Laser, Welding, Casting, Metal AM | Jacksonville, FL | BendingLaserWeldingCastingMetal AM | - |
| Porter Machine Inc Milling, Casting, Grinding · ISO 9001, AS9100 | West Greenwich, RI | MillingCastingGrinding | ISO 9001, AS9100 |
| Precise Cast Prototypes & Engineering Inc Milling, Casting | Commerce City, CO | MillingCasting | - |
| Precision Components & Assemblies, Inc Milling, Turning, Laser, Welding, Casting, Finishing, Assembly | Saint Peters, MO | MillingTurningLaserWeldingCastingFinishingAssembly | - |
| Princeton Tool Inc Milling, Waterjet, Casting, EDM, Grinding, Assembly · AS9100, NADCAP | Mentor, OH | MillingWaterjetCastingEDMGrindingAssembly | AS9100, NADCAP |