Sonoff S-MATE switch module, eWeLink, CR2032 battery powered

The Sonoff S-MATE fits in the wall box behind an ordinary wall switch and pairs with a Sonoff MINI R3 switch, sold separately. That lets the regular switch control the device connected to the MINI R3 over the eWeLink-Remote signal, even when the internet connection is down. It works with one, two and three-button switches and has a range of up to 50 m.

The maker highlights: it runs on a CR2032 battery and needs no neutral wire, so it also suits older wiring. One button can switch the device on and off while the others trigger scenes in the eWeLink app.

• Power. CR2032 (3 V) battery
• Switches. 1, 2 or 3-button
• Range. up to 50 m
• Input/output. 100–240 V ~50/60 Hz, max 16 A
• Operating temperature. −10…40 °C
• Dimensions. 54 × 45 × 24 mm
• Manufacturer code. S-MATE