Sensor window is at water outlet allowing easy and fast activation, self-setting appropriate sensor field within 20 seconds by pressing the button on the control box for 3 seconds after finishing installation.
 

The sensor range of this faucet is self-adjusting to it's environment and can be sensitive to environmental changes of light and reflective surfaces, it also detects water wastage. Neoperl flow regulator ensures water usage. Stable sensor technology prevents unintended operation.