Sixteen switched channels off one board, native MQTT, and a wired ethernet port. This is what goes in when a job needs real relay control and a fistful of smart plugs won't do. What it's for Fixed loads — lighting circuits, extractor fans, immersion heaters, underfloor zones, irrigation. Anything screwed to the building rather than plugged into a socket. It mounts in or beside the consumer unit and disappears. What it works with Home Assistant over MQTT — the usual route, and the one we use ESPHome — flash it and it appears as a native device Tasmota, Arduino IDE, or your own ESP32 firmware Wired ethernet or WiFi. Use the ethernet. Notes from fitting these Use the ethernet port. WiFi works, but a relay board controlling heating is not the place to rely on a wireless link. It needs an external 12V DC supply. Not included — a DIN-rail PSU is the tidy answer. The "with case" option is worth the few pounds if it's going anywhere near a customer's eyeline or anywhere dusty. This is an electrical job, not a plug-in job. If you're not competent working in a consumer unit, get someone who is. Specification ESP32 based, 16 relay outputs Ethernet + WiFi + Bluetooth Digital inputs (dry contact), analogue input, RS485, I2C, 433MHz options depending on variant 12V / 24V DC input CE, FCC, RoHS Delivery & import charges UK — free delivery. Price includes UK VAT at 20%. EU & international — free delivery. Your country's import VAT and any duty are not included and may be collected by the carrier before delivery. Please check your local thresholds before ordering. Dispatched direct from our supplier. Typical delivery 10–20 working days. SynkHaus is a smart home and solar installer. We sell the parts we fit ourselves.