THREE DIAMONDS

FILTERS, STRAIN METERS, MICROSCOPES, PHOTO-ELASTICITY INSTRUMENTS, POLARIZING PLATES, POLARIZING TEACHING TOOLS, CONSTANT TEMPERATURE OVENS, FURNACES FOR EXAMINATION, TELESCOPES, PRISMS, MAGNIFYING GLASSES, CAMERAS, FLASHING APPARATUS, MOVING PICTURE CAMERAS, MOVING PICTURE PROJECTORS, THERMOMETERS, BALANCES, REVOLUTION-INDICATORS, SPEED METERS, PHOTOMETERS, FLOWMETERS, AUTOMATIC HEAT REGULATORS, AUTOMATIC VACUUM REGULATORS, PROGRAM REGULATORS, MATERIAL TESTING MACHINES, SURVEYING INSTRUMENTS, ELECTROCARDIOGRAPHS, CLINICAL THERMOMETERS, KNEADERS, ULTRAVIOLET MEDICAL TREATMENT INSTRUMENTS, INFRARED RAY MEDICAL TREATMENT INSTRUMENTS, WATTMETERS, INTEGRATING WATTMETERS, PHASE METERS, FREQUENCY METERS, AMMETERS, VOLTMETERS, WAVE MEASURING METERS, OSCILLATORS, MAGNETIC MEASURING METERS, ANTENNA METERS, RESISTANCE MEASURING METERS, CAPACITY MEASURING METERS, TUBE TESTERS, AVOMETERS, AND OSCILLOGRAPHS