Model HD 2304.0 -Portable Pressure Thermometer

The keyboard of the Manometer – Thermometer Model HD2304.0 is composed of double-function keys. The function on the key is the "main function", while the one above the key is the "secondary function". When the instrument is in standard measurement mode, the main function is active. Once the Settings Menu has been opened, by pressing simultaneously the DATA+UNIT keys, the secondary function is enabled.