Plug-in resistance thermometers are very commonly used in machinery and systems, in plastic injection moulding and for temperature monitoring in packaging systems. The measuring resistor chosen is installed in a brass sleeve. A spring is pushed onto the wire that rests on the brass sleeve and which is connected with a bayonet cap. The thermometer is guided through a mounting adapter and secured by the bayonet cap. This configuration offers versatile adaptation of the installation length. Movements can also be compensated as a result.