I have 12 of these showing up as devices that I control and as z-wave repeaters for a total of 24 devices.
To make them work follow these steps.
Go to add a device.
Select IRIS.
Select plug.
Hold the front button in as you plug it in and release it when it turns blue. It should flash blue a few times and eventually pair as a device
Make sure the blue light is on and go to add a device again.
Select IRIS.
Select plug.
Push the front button eight times fast and wait for a while and it will pair up as a z-wave repeater this time.
Repeat these steps if it doesn’t work the first time.