Calibratable room temperature measuring transducer THERMASGARD® RTM 1 with continuous output, with / without optional display for indicating the actual temperature, in an elegant enclosure made of plastic, with snap-on lid, base with 4-hole attachment, for installation on vertically or horizontally installed in-wall flush boxes, with predetermined breaking point for on-wall cable entry or in an enclosure made of stainless steel (top and bottom parts are stainless steel, the cover is screwed on), vandal-proof version e.g. for schools, barracks and public buildings. This room temperature transmitter / residential temperature sensor is used to detect / display the temperature in closed, dry rooms, in apartments, offices, supermarkets and business facilities.