*** Please Note: This device includes an adapter for seamless integration with your home's pre-existing wall frames. This model includes an adapter for Legrand brand wall frames. The Shelly BLU Wall Switch 4 connects to other Shelly devices on the network through BLE (Bluetooth) technology and contains four buttons, each of which supports multi-click (single, double, triple and long-press clicks) for a total of 16 possible triggers. Unlike Shelly's other wall switches, the Shelly BLU Wall Switch 4 requires no wiring and does not contain a bracket for a Shelly device on the back; instead, this switch contains built-in Bluetooth technology, and be configured through the web interface to wirelessly trigger individual appliances, multiple Shelly devices, or synchronised Smart Scenes. This wall switch can be mounted on the wall by using the included adapter. This model's adapter is compatible with Shelly and Legrand (Niloe) switch frames.