Explanatory notes
… gauges ( heading 90.15 ); (c) Thermometers, pyrometers, barometers, hygrometers and psychrometers ( heading 90.25 ); … (turbine‑type, piston‑type, etc.), but the majority are based on the principle of differential pressure. These … (float, diaphragm, differential pressure, oscillating ring balance or flow transmitters, etc., type). (2) Variable area …