Computer-controlled apparatus for testing and measuring the thickness of skin via radio frequency signals, sonar, concentrations of gas and liquids, audio signals not for medical use; Altimeters; Anemometers; Barometers; Distance measuring apparatus; sensors for measuring distance, not for medical use; Range finders; Gasometers; Level indicators; bubble levels; Hygrometers; Clinometers; Surveyors' levels; Planimeters; audio speakers; Soil sampling instrument for measuring soil nutrients, mois...