PRECISION FLUID SYSTEM COMPONENTS AND ASSEMBLIES-NAMELY, SERVOVALVES, PROPELLANT VALVES, CONTROL VALVES, ACTUATORS, FILTERS, SWITCHES, REGULATORS, GAUGES, VESSELS; FUEL SYSTEM CONTROL VALVES AND MEASUREMENT APPARATUS; [ FIRE SUPPRESSION AND CONTROL UNITS; ] [ GAS METERS AND REGULATORS AND PARTS THEREOF; PRESSURE REGULATORS; NUMERICAL CONTROL UNITS FOR MACHINE TOOLS; NUMERICAL CONTROLS FOR TURRET LATHES; ELECTRONIC AND HYDRAULIC MACHINE TOOL CONTROL UNITS; OPTICAL DUPLICATORS; OPTICAL COMPARATORS; SPECTACLES; EYEGLASSES; EYEGLASS FRAMES AND PARTS THEREOF; CASES FOR HOLDING SPECTACLES AND EYEGLASSES; LENSES; OPHTHALMIC LENS AND LENS BLANKS; OPTICAL MACHINERY USED FOR ADJUSTING AND TESTING LENSES AND LENS MOUNTINGS FOR EYEGLASSES AND SPECTACLES-NAMELY, LENS MARKERS, LENS TESTING UNITS, GAUGERS AND GAUGE RACKS, AND PARTS FOR ALL OF THE FOREGOING; OPTICAL INSTRUMENTS AND DEVICES FOR TESTING AND EXAMINING EYES, SPECTACLES, EYEGLASSES, AND PARTS THEREFOR; PERSONAL SAFETY PRODUCTS AND EQUIPMENT FOR HEARING, EYE, RESPIRATORY, AND HEAD PROTECTION-NAMELY, INDUSTRIAL SAFETY GOGGLES, FACE SHIELDS, MAGNIFYING LENS FOR WELDERS' HEADGEAR, WELDERS' HELMETS, SAFETY HATS AND CAPS, WELDING GLOVES, AND RESPIRATORS; ELECTRICAL RACEWAY PRODUCTS AND SYSTEMS-NAMELY, METAL RACEWAYS, FLOOR BOXES, UNDERFLOOR DUCTS, FLOOR FITTINGS, JUNCTION BOXES, SERVICE POLES; ADAPTORS; ELBOWS; OFFSETS; ] INERTIAL INSTRUMENTS; ELECTROMAGNETIC DEFENSE UNITS; AEROSPACE ANTENNAS; ELECTRO OPTICS; HIGH ENERGY LASER BEAM SYSTEMS; [ DIGITAL WATCH MODULES; ] DIGITAL FREQUENCY SYNTHESIZERS; OSCILLATORS, CRYSTALS AND FILTERS; TEMPERATURE INDICATORS; VOLTMETERS, PRECISION TIMERS AND STOPWATCHES; THERMOCOUPLE INDICATORS; COUNTERS; TRACKING COMPARATORS; DIGITAL PRESETS; REMOTE DISPLAYS; FREQUENCY METERS; TACHOMETERS; [ TAPE-PROGRAMED ELECTRONIC UNIT FOR CHECKING THE OPERATING SYSTEM OF A DIESEL ELECTRIC LOCOMOTIVE; ] ELECTRONIC DEFENSE DETECTION UNIT FOR AIRCRAFT SERVICE FITTINGS, BEING PARTS OF GAS AND WATER METERS