I wasn't even sure if I needed this or not, but I bought it. It is not very expensive but it works extremely well. Since the light switches are repeaters and I have a few of them in the house, I feel like I have a pretty well connected Aqara Zigbee system. Once I get the M3 hub, I will move the location of the E1 hub just to extend the system a little further. But so far it is working very well.