LEDDim Smart Master is a smart dimmer for mounting to wall box (EU) Bluetooth communication (BLE) and control via App.The dimmer has four buttons surrounding the knob which can be programmed via the app to control other devices, scenes, away function etc. Minimum, maximum and start up level can be set by the app. LEDDim Smart Master can be programmed to be master for other devices, meaning they would turn ON/OFF or dim accordingly, this gives the possibility of stairway function etc.