ELECTRICAL OR ELECTRONIC COMPONENTS MOUNTED OR HOUSED IN ORDER TO FACILITATE THEIR USE FOR INSTRUCTIONAL AND INSTRUMENTATION PURPOSES, NAMELY; AMPLIFIERS, OSCILLOSCOPES, CATHODE RAY TUBES, ELECTRONIC DIGITAL READOUTS, OSCILLATORS, SIGNAL DECODERS, ELECTRONIC INTERFACES, MICROCOMPUTER INTERFACES, ELECTRONIC CONVERTERS, ULTRAVIOLET LAMPS, PHOTOELECTRIC CELLS, RADIO RECEIVERS, ELECTRICAL POWWER SUPPLIES, TIMERS, LASERS, FIBER OPTIC CABLES, FIBER OPTIC COMMUNICATION BOARDS, GEIGER TELLERS, RATER METERS, GEIGER MULLER TUBES, GEIGER MULLER TUBE HOLDERS, GEIGER MULLER SCREENED LEADS, GEIGER MULLER TUBE POWER SUPPLIES, DIGITAL SCALER-TIMERS, SOLID STATE DETECTORS, GEIGER TELLER CARRYING CASES, ENVIRONMENTAL KITS, CASES FOR ENVIRONMENTAL KITS, LIGHT METERS, PH METERS, OXYGEN MEASURERS, TEMPERATURE MEASURERS, CONDUCTIVITY MEASURERS, SOUND MEASURERS, GEOPHYSICS MODULES, ELECTRODES AND TRANSDUCERS FOR GEOPHYSICAL SURVEYING, INCLUDING SPONTANEOUS POTENTIALS, EQUIPOTENTIAL PLOTTING, RESISTIVITY SURVEYING, REFRACTION SEISMOLOGY, PROTON MAGNETOMETRY AND RADIOACTIVITY, VIBRATION GENERATORS AND PARTS AND FITTINGS THEREFOR, STROBOSCOPES, MICROWAVE TRANSMITTERS AND STANDS THEREFOR, MICROWAVE RECEIVERS AND STANDS THEREFOR, MICROWAVE PROBE RECEIVERS, POLARIZATION GRILLS, MICROWAVE REFLECTORS, BRAGG SCATTERING LENSES AND TURNTABLES, MICROWAVE REFRACTION PRISMS, LENSES ND BLOCKS, MICROWAVE WAVE GUIDES, FRESNEL ZONE PLATES, ULTRASONIC TRANSMITTERS, RECEIVERS, TRANSDUCERS, PLATES, REFLECTORS, MAGNETIC FIELD MEASURERS, COMPUTER PROGRAMS, CONSTRUCTION KITS, ULTRAVIOLET EXPOSURE UNITS, PHOTOETCHERS FOR ETCHING GROOVES OR TRACKS TO FORM ELECTRICALLY CONDUCTIVE PATHWAYS ON BOARDS, FLUID VELOCITY METERS, CHROMATOGRAPHS, MEDICAL APPLIANCES, TECHNOLOGY TEACHING EQUIPMENT ESPECIALLY ADAPTED FOR THE EDUCATIONAL ENVIRONMENT, NAMELY HIGH VISIBILITY DIALS AND FAILSAFE BIOLOGICAL AMPLIFIERS, PNEUMATIC AND HYDRAULIC APPARATUS; ELECTRICAL OR ELECTRONIC COMPONENTS FOR INSTRUCTIONAL AND INSTRUMENTATION PURPOSES NOT SO HOUSED, NAMELY; CAPACITORS INDUCTANCES, TRANSFORMERS, RESISTERS, SOLID STATE ELECTRONIC APPARATUS, SWITCHES, COMPUTERS, THYRATRONS, VACUUM TUBES COMPONENTS ENCLOSURES, PLUGS, SOCKETS, CONNECTING LEADS, BATTERIES, METERS, OPTICALS, CABLES, GAS FILLED TUBES, LOUD SPEAKERS, MICROPHONES, ELECTRONIC METERS ANTENNAE, THERMONIC VALVES, CRAFT TOOLS, LABORATORY TABLES AND BENCHES, COMPUTER-AIDED DESIGN PROGRAMS