Includes
Liquid Level Float Instruments; Revolution Counters; Speedometers; Rotation Measuring Instruments and Apparatus; Oxygen Flow Indicators; Tachometers, including Engine Tachometers.

Excludes
Combination Instruments; (FSC 6695); Meteorological Instruments (FSC 6660); and Automatic Control Valves (FSG 48).

Possible NAICS Codes
334519 – Other Measuring and Controlling Device Manufacturing
334513 – Instruments and Related Products Manufacturing for Measuring, Displaying, and Controlling Industrial Process Variables
334514 – Totalizing Fluid Meter and Counting Device Manufacturing
336413 – Other Aircraft Parts and Auxiliary Equipment Manufacturing
333618 – Other Engine Equipment Manufacturing
334610 – Manufacturing and Reproducing Magnetic and Optical Media
332722 – Bolt, Nut, Screw, Rivet, and Washer Manufacturing
333120 – Construction Machinery Manufacturing
333310 – Commercial and Service Industry Machinery Manufacturing
334516 – Analytical Laboratory Instrument Manufacturing

Includes
Thermometers, including Engine Thermometers; Pressure Gages; Thermocouple Leads; Resistance Bulbs.

Excludes
Clinical Thermometers; (FSC 6515); Thermostatic and Differential Pressure Switches (FSC 5930); and Meteorological Instruments (FSC 6660).

Possible NAICS Codes
334513 – Instruments and Related Products Manufacturing for Measuring, Displaying, and Controlling Industrial Process Variables
334519 – Other Measuring and Controlling Device Manufacturing
334512 – Automatic Environmental Control Manufacturing for Residential, Commercial, and Appliance Use
336413 – Other Aircraft Parts and Auxiliary Equipment Manufacturing
333618 – Other Engine Equipment Manufacturing
332722 – Bolt, Nut, Screw, Rivet, and Washer Manufacturing
333310 – Commercial and Service Industry Machinery Manufacturing
333998 – All Other Miscellaneous General Purpose Machinery Manufacturing
334511 – Search, Detection, Navigation, Guidance, Aeronautical, and Nautical System and Instrument Manufacturing

Includes
Clocks; Job Recording Devices; Time Recorders; Time Stamps; Watch and Clock Movements; Watches.

Possible NAICS Codes
334519 – Other Measuring and Controlling Device Manufacturing
334419 – Other Electronic Component Manufacturing
334511 – Search, Detection, Navigation, Guidance, Aeronautical, and Nautical System and Instrument Manufacturing
334515 – Instrument Manufacturing for Measuring and Testing Electricity and Electrical Signals
332216 – Saw Blade and Handtool Manufacturing
334513 – Instruments and Related Products Manufacturing for Measuring, Displaying, and Controlling Industrial Process Variables

Includes
Contactors: Motor Controllers; Power Servomechanisms; Switchgear; Voltage Regulators.

Excludes
Automatic Pilot Mechanisms; Relays; Resistors.

Possible NAICS Codes
334519 – Other Measuring and Controlling Device Manufacturing
335312 – Motor and Generator Manufacturing
335314 – Relay and Industrial Control Manufacturing
335999 – All Other Miscellaneous Electrical Equipment and Component Manufacturing
332510 – Hardware Manufacturing
332722 – Bolt, Nut, Screw, Rivet, and Washer Manufacturing
335313 – Switchgear and Switchboard Apparatus Manufacturing
333618 – Other Engine Equipment Manufacturing
335311 – Power, Distribution, and Specialty Transformer Manufacturing
334413 – Semiconductor and Related Device Manufacturing

Includes
Destructive and Nondestructive Inspection Equipment such as Fluorescent Penetrant Inspection Units; Magnetic Inspection Units; Industrial X-Ray Machines; Industrial X-Ray Film; Tensiometers; Material Hardness Testers.

Excludes
General purpose Measuring Tools (FSC 5210) and Precision Measuring Tools and Inspection Gages (FSC 5220).

Possible NAICS Codes
334519 – Other Measuring and Controlling Device Manufacturing
334516 – Analytical Laboratory Instrument Manufacturing
334517 – Irradiation Apparatus Manufacturing
334515 – Instrument Manufacturing for Measuring and Testing Electricity and Electrical Signals
334513 – Instruments and Related Products Manufacturing for Measuring, Displaying, and Controlling Industrial Process Variables
333998 – All Other Miscellaneous General Purpose Machinery Manufacturing
332722 – Bolt, Nut, Screw, Rivet, and Washer Manufacturing
541380 – Testing Laboratories and Services
333310 – Commercial and Service Industry Machinery Manufacturing
336413 – Other Aircraft Parts and Auxiliary Equipment Manufacturing

Includes
Flow-Pressure Instruments; Taximeters; Dynamometers.

Excludes
Dental, Medical, Surgical, and Veterinary Instruments.

Possible NAICS Codes
334519 – Other Measuring and Controlling Device Manufacturing
334513 – Instruments and Related Products Manufacturing for Measuring, Displaying, and Controlling Industrial Process Variables
334515 – Instrument Manufacturing for Measuring and Testing Electricity and Electrical Signals
334516 – Analytical Laboratory Instrument Manufacturing
336413 – Other Aircraft Parts and Auxiliary Equipment Manufacturing
334419 – Other Electronic Component Manufacturing
333618 – Other Engine Equipment Manufacturing
336411 – Aircraft Manufacturing
334511 – Search, Detection, Navigation, Guidance, Aeronautical, and Nautical System and Instrument Manufacturing
333998 – All Other Miscellaneous General Purpose Machinery Manufacturing

Includes
Laboratory Glassware; Laboratory Funnels; Laboratory Furnaces; Glass Beads; Laboratory White Sand; Litmus Paper; Paper Filters; Insect Transfixion Pins; Laboratory Glass Wool; Laboratory Furniture, except Dental Laboratory.

Excludes
Instruments covered by other classes in group 66; Dental Laboratory Equipment; Laboratory Scales and Balances; In Vitro Diagnostic Substances and Reagents.

Possible NAICS Codes
423450 – Medical, Dental, and Hospital Equipment and Supplies Merchant Wholesalers
339999 – All Other Miscellaneous Manufacturing
334516 – Analytical Laboratory Instrument Manufacturing

Includes
Radiac Equipment; Gas Detecting Equipment; Land Mine Detecting Equipment

Excludes
Manual Gas Alarms (FSC 6350).

Possible NAICS Codes
334511 – Search, Detection, Navigation, Guidance, Aeronautical, and Nautical System and Instrument Manufacturing
334519 – Other Measuring and Controlling Device Manufacturing
334516 – Analytical Laboratory Instrument Manufacturing
314999 – All Other Miscellaneous Textile Product Mills
334517 – Irradiation Apparatus Manufacturing
334513 – Instruments and Related Products Manufacturing for Measuring, Displaying, and Controlling Industrial Process Variables
333998 – All Other Miscellaneous General Purpose Machinery Manufacturing
562211 – Hazardous Waste Treatment and Disposal

Includes
Acidity (pH) Meters; Gas Analyzers; Alkalinity Measuring Instruments; Colorimeters.

Excludes
Gas Detecting Equipment; Manual Gas Alarms; Chemicals; In Vitro Diagnostic Substances and Reagents.

Possible NAICS Codes
334516 – Analytical Laboratory Instrument Manufacturing
334519 – Other Measuring and Controlling Device Manufacturing
423450 – Medical, Dental, and Hospital Equipment and Supplies Merchant Wholesalers
339113 – Surgical Appliance and Supplies Manufacturing
334515 – Instrument Manufacturing for Measuring and Testing Electricity and Electrical Signals
334513 – Instruments and Related Products Manufacturing for Measuring, Displaying, and Controlling Industrial Process Variables
325413 – In-Vitro Diagnostic Substance Manufacturing

Includes
Meteorological Balloons; Radiosonde Sets; Radarsonde Sets.

Possible NAICS Codes
334519 – Other Measuring and Controlling Device Manufacturing
334511 – Search, Detection, Navigation, Guidance, Aeronautical, and Nautical System and Instrument Manufacturing
334513 – Instruments and Related Products Manufacturing for Measuring, Displaying, and Controlling Industrial Process Variables
334516 – Analytical Laboratory Instrument Manufacturing
326299 – All Other Rubber Product Manufacturing
924120 – Administration of Conservation Programs
335999 – All Other Miscellaneous Electrical Equipment and Component Manufacturing
811210 – Electronic and Precision Equipment Repair and Maintenance

Includes
Crushers and Mills for Chemical Materials; Pharmaceutical Briquetting and Tabletting Presses; Chemical Explosives Manufacturing Machinery.

Excludes
Construction Materials Crushers, Mills and Pulverizers; Plastics Products Manufacturing Machinery; Pharmaceutical Products Wrapping and Packaging Machinery; Laboratory and Shop Type Mills and Mixers.

Possible NAICS Codes
334519 – Other Measuring and Controlling Device Manufacturing
325412 – Pharmaceutical Preparation Manufacturing
325998 – All Other Miscellaneous Chemical Product and Preparation Manufacturing
456199 – All Other Health and Personal Care Retailers
339112 – Surgical and Medical Instrument Manufacturing
334516 – Analytical Laboratory Instrument Manufacturing
332999 – All Other Miscellaneous Fabricated Metal Product Manufacturing

Includes
Anti-intrusion Alarm Systems; Foghorns; Gongs; Chimes; Bells; Burglar Alarm Systems; Fire Alarms; Police Alarm Systems; Sounding Devices; Manual Gas Alarms; Landing Wands.

Excludes
Loran; Radar; Sonar; Engine Oil and Fuel Warning Devices; Aircraft Oxygen Warning Devices.

Possible NAICS Codes
561621 – Security Systems Services (except Locksmiths)
334290 – Other Communications Equipment Manufacturing
335311 – Power, Distribution, and Specialty Transformer Manufacturing
334519 – Other Measuring and Controlling Device Manufacturing
334512 – Automatic Environmental Control Manufacturing for Residential, Commercial, and Appliance Use
334511 – Search, Detection, Navigation, Guidance, Aeronautical, and Nautical System and Instrument Manufacturing
334220 – Radio and Television Broadcasting and Wireless Communications Equipment Manufacturing
333120 – Construction Machinery Manufacturing
541519 – Other Computer Related Services
335999 – All Other Miscellaneous Electrical Equipment and Component Manufacturing

Includes
Test Leads and Test Lead Attachments; Test instruments designed for communication equipment; Test instruments designed for use with electronic equipment classified in two or more FSC groups.

Excludes
Radiac Equipment.

Notes
This class includes all "basic" types of electrical and electronic test instruments, such as ammeters, voltmeters, ohmmeters, multimeters, and similar instruments, even if specially designed. Excluded from this class by the modifier "except specially designed" are test instruments, other than "basic" instruments, which are specially designed for use with atomic ordnance, fire control, guided missile, motor vehicle, aircraft, or photographic equipment. Such specially designed test instruments are to be classified in other classes in the Federal Supply Classification. This class includes communications test equipment, infrared test equipment designed for communication, and night vision maintenance and test specialized equipment.

Possible NAICS Codes
334515 – Instrument Manufacturing for Measuring and Testing Electricity and Electrical Signals
334514 – Totalizing Fluid Meter and Counting Device Manufacturing
334412 – Bare Printed Circuit Board Manufacturing
334513 – Instruments and Related Products Manufacturing for Measuring, Displaying, and Controlling Industrial Process Variables
334519 – Other Measuring and Controlling Device Manufacturing
334516 – Analytical Laboratory Instrument Manufacturing
334220 – Radio and Television Broadcasting and Wireless Communications Equipment Manufacturing
336413 – Other Aircraft Parts and Auxiliary Equipment Manufacturing
334511 – Search, Detection, Navigation, Guidance, Aeronautical, and Nautical System and Instrument Manufacturing
334290 – Other Communications Equipment Manufacturing

Includes
Drawing Instruments, Drafting Tools; Engineering and Architectural Scales; Levels; Transits; Photogrammetric Instruments; Astrolabes; Level Rods; Plane Tables; Surveying Altimeters; Theodolites.

Excludes
Surveyors' Tapes.

Possible NAICS Codes
334516 – Analytical Laboratory Instrument Manufacturing
334519 – Other Measuring and Controlling Device Manufacturing
334511 – Search, Detection, Navigation, Guidance, Aeronautical, and Nautical System and Instrument Manufacturing
334515 – Instrument Manufacturing for Measuring and Testing Electricity and Electrical Signals
332510 – Hardware Manufacturing
334513 – Instruments and Related Products Manufacturing for Measuring, Displaying, and Controlling Industrial Process Variables
334220 – Radio and Television Broadcasting and Wireless Communications Equipment Manufacturing
541370 – Surveying and Mapping (except Geophysical) Services
423490 – Other Professional Equipment and Supplies Merchant Wholesalers

Includes
All Engine Instruments, including Aircraft, Marine, and Vehicular; Fuel Pressure Gages; Manifold Pressure Gages; Oil Pressure Gages; Fuel Mixture Indicators; Engine Oil and Fuel Warning Devices.

Notes
Instruments designed for use on both engines and other than engines are not included in this class and should be classified in the appropriate instruments class of group 66.

Possible NAICS Codes
333618 – Other Engine Equipment Manufacturing
334519 – Other Measuring and Controlling Device Manufacturing
335312 – Motor and Generator Manufacturing
336411 – Aircraft Manufacturing
336413 – Other Aircraft Parts and Auxiliary Equipment Manufacturing
334515 – Instrument Manufacturing for Measuring and Testing Electricity and Electrical Signals
332722 – Bolt, Nut, Screw, Rivet, and Washer Manufacturing
334514 – Totalizing Fluid Meter and Counting Device Manufacturing
334511 – Search, Detection, Navigation, Guidance, Aeronautical, and Nautical System and Instrument Manufacturing
332510 – Hardware Manufacturing