| | Mattox & Moore Inc (Indianapolis, IN) Veterinary paste implant guns, vitamins & egg quality testing instruments | |
| | Mednext Inc (West Palm Beach, FL) Medical instruments | |
| | Mercury Instruments Inc (Fairfax, OH) Electronic & mechanical pressure temperature volume recording & billing instruments | |
| | Metermaster Inc (Troy, MI) Thermocouples, electrical & electronic instruments | |
| | Micro Dynamics Instrumentation (Sanford, FL) Electronic automotive distance measuring instruments | |
| | Micro Tool Engineering Inc (Riviera Beach, FL) General machining; medical equipment & instruments; aerospace & aircraft parts | |
| | Miter Inc (Warsaw, IN) Dental implant instruments & bone grafting supplies | |
| | Moritz Corp (Perkasie, PA) Manufactures electronic aviation instruments | |
| | Morrow Technologies Corp (Largo, FL) Computerized signage systems, test & measurement instruments | |
| | National Patent Analytical Sys (Mansfield, OH) Manufactures breath alcohol instruments | |
| | Neuro Kinetics Inc (Pittsburgh, PA) Medical instruments | |
| | Noramar Co (Chagrin Falls, OH) Analytical instruments | |
| | Nordent Manufacturing Inc (Elk Grove Vlg, IL) Dental & surgical instruments | |
| | Nuclear Measurements Corp (Indianapolis, IN) Radiation measuring instruments for industry & science | |
| | Overhoff Technology Corp (Milford, OH) Process control & radiation measurement electronic instruments, electronic design service | |
