These are going to be fun.
They're inexpensive WiFi-controlled power adapters for home automation and energy management. The wall socket version on the left plugs in under an appliance to provide remote on/off. The version on the right needs to be wired in but also has the ability to monitor volts, amps and watts.
Philosophically I would have preferred these to be using LoRaWAN rather than WiFi but the tech and the cost of LoRa devices hasn't reached the adoption point for me yet.
In contrast this WiFi gear is remarkably capable and inexpensive. The S26 and the POWR2 pictured here cost $NZ7 and $NZ15 respectively, and Sonoff has a range of other devices
to perform various functions.
The key attraction is these devices are programmable, and there's a community of people doing so with an aftermarket open source firmware called Tasmota
. Because of this firmware, the Sonoff devices can be integrated with the energy management system I'm already using.