Compact, small mechanical thermostat offering a high response accuracy/time, small switch temperature difference, and a very long service life (switching cycles). This thermostat of temperature class T6 (85 ° max.) is utilised for the regulation of heaters within control and switch cabinets, as well as measuring equipment located in areas with explosion hazard, underground mines and mines susceptible to firedamp. The high switching performance allows for direct control of heaters.