Acetylene regulators; Barometers; Dual amplifier balancers; Electronic slag detectors for use in the metal smelting and steelmaking process; Gas detectors for detecting the presence of gas; Instruments for detecting and measuring two-dimensional distribution of force and pressure; Nitrogen concentration detectors; Oxygen regulators; Static voltage regulators; Thermometers, not for medical purposes; Unloading check valves for the outlets of air compressors; Voltage regulators