*** Please Note:This model includes a standalone adapter - a back plate for if the wall switch is to be used as a standalone remote control without affixing it to a wall. 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 is designed to be used as a standalone pocket-sized remote control.