Shelly Plus i4 DC is a low-voltage four-input Wi-Fi controller for turning ordinary switches and buttons into smart-home scene and action triggers. It does not switch a load itself; instead, its four inputs can activate scenes, synchronised actions or more complex trigger logic across Shelly devices and HTTP- or MQTT-controlled systems.

Powered from 5–24 V DC, it fits into standard electrical wall boxes and other compact spaces. Multi-click support provides up to 16 actions, while scripting, webhooks, MQTT, an embedded web interface, Wi-Fi and Bluetooth give it flexible local and network automation options.