26.510Level 526.51Manufacture of instruments and appliances for measuring, testing and navigation26.51001Manufacturing precision scales of the type used in laboratory26.51002Manufacture of microscopes other than optical and diffractograms26.51003Manufacture of instruments and navigation, meteorological, geophysical, etc. (Geodesy, oceanography, hydrology, topography, surveying, radar, sonar, etc.)26.51004Manufacture of electricity meters, water, gas, gasoline, etc.26.51005Manufacture of devices and optical measuring instruments and control26.51006Manufacture of other instruments, apparatus or measuring machines, control or test: hydrometers, areometers, thermometers, barometers, revolution, taximeters, pedometers, etc.