So I'm giving the product a 5 star at this time because it simply works great, as you'd expect a HomeKit accessory to do and the ony reason I would change that rating is if it fails. I'm of course hoping it'll last years (only been installed for a few days at this point) but it's an electronic switch, who knows, but for the price other than the hassle of installing a new one it's a bargain. This review/experience is ONLY about using with HomeKit. The back of the switch is bulky, just like ALL electronic switches. They've got to put the circuitry somewhere. So if your wall box is typical (like mine) and the electrician(s) who wired it used #12 solid core copper wire, it's stiff and can be difficuly to move but with some finesse and moving of wires, it'll fit, at least mine did. The design of the switch was different than what I expected (albeit a really neat design) only because all switches (Lutron, Leviton, etc) that look like this have always been a rocker, up/down, to toggle on/off. You should be able to see in the picture that the switch "looks" like the top is "rockered" in indicating the switch to be on but the reality is the top is hinged and doesn't move and only the bottom of the switch moves. Push the bottom once, it's on, push it again, it's off but it always returns to the position as shown in the picture. This is actually a great design since you can manually operate the switch but also have HomeKit operate the switch and the position of the switch is never "out of sync" with whether the lights are on or off. The only indicator "other than the lights themselves" is the LED that's in the switch and by default it's on when the switch is on and off when off. That can be changed but not in the Home app. A standard single-pole manual wall switch usually has just two wire, typically both black which simply breaks the circuit to the light or applicance and the neutral back from the light is pigtailed with other neutrals in the box. That's my setup. This switch from Refoss has four leads out of the box on the back, brown, black, white and green. The brown and black wires connect to the two black wires that were connected to the old switch. The wires are labled line in and line out but I don't know that it makes any difference. Either I just got lucky or it doesn't matter because I never checked current (BEFORE SWITCHING OFF THE BREAKER) so I don't know which of my two black wires actually had current with the breaker on but as said, either I got luck or it doesn't matter with I suspect the latter to be the case. YOU DO HAVE TO CONNECT THE WHITE WIRE TO A NEUTRAL CONNECTION IN YOUR BOX. Since I have three switches in this box I had several neutral pigtails with wire nuts in my box so I simply picked the easiest one to get to, took the wire nut off, added the white wire from the Refoss switch put the wire nut back on and done. The Refoss also has a green wire (ground), don't know that it's actually required but if you've got a ground in your box I'd use it, I did. The switch does come with a faceplate if it's the only switch in the box. You'll need to buy seperately if you need something like shown in my picture. Once installed and power back on, the LED in the switch did flash between amber and green just as he instructions said it would so on to setup. So if you're a HomeKit user (shouldn't be reading this if not) you know that typically to add a new accessory, you touch the plus sign, touch add accessory, scan the QR code and pretty much you're done. I guess the only two complaints I have about the Refoss HomeKit setup is nowhere was there a HomeKit QR code to scan, not on the switch, not on a label in the box nor on the box itself, but, molded into the switch body and painted black was the 8 digit HomeKit setup code and here's the second complaint. To be able to scan the 8 digit code with the Home app will do, it expects that 8 digit code to be in the format xxx-xx-xxx. The code on the Refoss switch was 4 digits in a row with the other 4 digits in a row just below the first 4. The Home app would NOT scan this no matter how I tried which means you then have to touch "I don't have a code or cannot scan" which takes you to the next page where you can touch under Manual Code, "enter code" and you can, and that works. On the switch itself Refoss could have simply put a stick on label on the box (back) of the switch, or put a label in the box but they didn't and this was the only complaint I have, at all. One user said his switch came with a HomeKit QR code, but mine didn't. You don't have to have the eHomeLife (manufacturers) app. That being said, the current version (iOS 13) of Apple's Home app will not perform manufacturers firmware updates. The Home app directs you to the manufacturers app for that process. So that being said, I did d'load the eHomeLife app and checked and my switch is up to date on firmware. So all in all, Refoss could improve the HomeKit setup process a little by including the HomeKit QR code but otherwise, the switch works GREAT and for the price. I don't see that you can go wrong.
