The ECL Application Keys, series A2xx can be used in ECL Comfort 210, ECL Comfort 296 and ECL Comfort 310. Most of the A2xx application keys give extended functionalities when used in ECL Comfort, such as additional temperature sensors and M-bus communication.The application parameters are stored in the controller and are not affected by power break.Different ECL application keys make it easy for the ECL Comfort Controllers hardware to run different applications. The ECL Comfort controller is loaded with the desired application by means of the ECL application key, which contains information about applications (simple application sketches are shown in the display), languages, factory settings and firmware.