Colorimeters; Flowmeters; Illuminometers; Ohmmeters; Wattmeters; Digital multimeters; Distance measuring apparatus; Electronic spectrophotometer for use in identifying and measuring colors; Frequency meters; Gas testing instruments; Measuring apparatus for temperature and humidity levels in gases and solid substances; Metal strength testing machines; Oscillographs; Radiation-measuring instruments; Resistance measuring instruments; Surveying instruments; Temperature sensors; Ultrasonic sensors...