I see two readily available smart outlets for matter that appear UL/ETL listed for US.
I have an older house and outlets are the tiny 60’s small boxes. They won’t hold most smart outlets, and I’ve had to cut several out and put in larger boxes which is a pain. Those were the TopGreener wifi outlets.
Does anyone have these outlets, and can tell me what size the inside is, and/or if you’ve put on any of the old style small metal outlet boxes if they fit? Or which is the smaller of the two?
I installed an Eve Energy Outlet. It provides leaders for the hot/neutral/ground connections, so those must be trimmed and/or coerced into the box along with their connectors. I came from a 1950s house with those tight aluminum boxes and that came to mind when installing the Eve in my current, newer house. It reminded me of installing Insteon outlets at my old house from a size, effort getting it to fit… meaning expect it to take effort to install, or adding a new jbox.
Eve provides wire nuts but I would get the flat push-in versions which take less room and connections less likely to be “stressed” apart.
Clarification about the Eve Energy Outlet: it’s Matter over Thread only, not wifi.
I’m not really using mine as an outlet, rather as a thread mesh router which it does a great job at. The outlets can be controlled and work as expected when remotely triggered.
Another thing to note is that the green LED “On” lights are really bright. Times 2 if both outlets are on.
Thanks. Yes, I knew they were Matter over Thread (I have two Thread Border Routers).
I wonder if the Tapo are smaller? Anyone know?
I just spent the last 20 minutes rummaging through my house, trying to find a pack of Tapo outlets, since I bought a massive number of their outlets, switches, etc to fully upgrade my parents’ house (they spend what feels like half their time just running around switching various lights and plug-in floor lamps on and off).
I could have sworn I had kept one pack at home, specifically so I could do a trial-run here first, but, if it is here, it seems to be exceptionally good at hiding. Probably doesn’t help that my place is currently a complete mess… 
Sorry I couldn’t be of help, but I’ll take another look around later today; if I do come across them, I’ll be sure to take measurements and post the dimensions/some pics for you.
EDIT:
I checked their site really quick, which managed to be singularly unhelpful, as, according to their specs, it is entirely two-dimensional:
“Product Dimensions (L x W x H)
128.7 × 84.7 mm”
I did manage to find a review of them, though, and, while they similarly seem to believe in their two-dimensionality in reporting the size, they did include a picture of it hanging out of what appeared to be an old-style metal outlet box - definitely looks pretty snug, but, depending on how much of a rats’ nest of wiring it will have to share space with, should be able to fit? Anyway, here’s the link:
EDIT 2:
The measurements given by TP-Link seem to just be the external dimensions with faceplate - did find this in the manual, though, for whatever it’s worth:
“Install only in a suitable UL Listed outlet box (suitable dimensions:
H > 2.95 in./75 mm, W >1.81 in./46 mm, D > 3.15 in./80 mm).”
Here’s the full manual, for reference:
https://manuals.plus/tp-link/tapo-p210m-smart-wi-fi-outlet-energy-monitoring-manual
Once I find the answer, and you have no more interest, you will trip over one of them and hurt your toe.
It’s part of the Matter standard. 
for the Tapo you can find a figure here
That’s pretty much the story of my life as well lol
I don’t see measurements; well other than Amazon who has a depth of 0.1" so…
I did see a photo but no dimensions.
I went ahead and ordered one, it comes Saturday, will know for sure then.
Thanks.
Here’s half the answer (it came a day early)…
First, it doesn’t have pigtails, but rather screw connectors (one on each side, and one ground on the bottom). They look suitable to stab rather than loop a wire and have a notch cut as though it is expected to allow two wires.
The size is roughly rectangular, not a lot of curves, and 44mm wide (side to side), 72mm tall (ground screw may add slightly to that), and 38mm deep (to the back of the back plate not including the metal grounding pads that should compress). There’s a roughly 5mm, 45 degree taper on the top and bottom (but not sides) that should help slightly with wires as that’s where these old boxes have their screw-down clamps.
I’m too tired this evening to pick a box and open it up to see if it fits. It’s about the size of the top greener’s that do not fit (I only have some switches out, not outlets, and it’s almost identical to those). So I am not optimistic. Though screw vs pigtails does give me a bit of hope.
More when I try it. Mayb e tomorrow, probably Sunday.
Linwood
Inovelli White series switches are like this (they don’t make outlets). No pigtails, just move wires over one at a time and mount the switch back in the jbox. Easy and fast! By far the easiest HA wired in devices I have ever installed.
Well, it’s close, but it will not fit. It hits on the sides slightly (the outlet may not be completely square), but worse the top and bottom hit. Even if they didn’t, the cross-nail that holds it to the wall is not deep enough for it to go all the way in.
I would end up having to cut these out and replace with a full size box. I’m not sure I have any more that I need badly enough to do that. Maybe.
I tried just hooking power up to it and went to scan the QR code and join my matter network and… wait, there’s no QR code. There’s none in the package, none anywhere.
I went with matter so I would not have to use yet another Chinese app on my phone, but starting to think they require it. Anyone know for sure?
But no QR code, and no pairing code anywhere I can find.
Manual says
Set Up Your Device via Matter
You can integrate your Tapo Matter device into your
preferred ecosystem, such as Amazon Alexa, Apple
Home, Google Home, and more.
Open your preferred smart home app and add the
device via the Matter QR code on the label in the
package. You can also find the Matter numeric code
by detaching the wallplate and unscrewing its bracket.
For more details and troubleshooting, please refer to the Matter QIG
or visit: TP-Link Matter Devices: Setup Guide, Hub Compatibility, and Tips
The manual says that, but there’s no QR code in the box. I’m on with their chat now, had me send photos of all sides.
There’s about 4 QR codes to download the tapo app. And one fake QR code as a matter example (pairing code 12345678901 or something like that).
Ah… I found it. Well, I found the pairing numbers.
See the plastic rectangular ring around the outlet? It’s held on by the two screws. Directly underneath it along one side is the 11 digit pairing code.
I paired it, it added immediately, and…
There’s NO ENERGY SENSORS.
What a waste of a lot of time. It says right on the box “Energy monitoring”.
Sigh…
Do not buy for Matter!
I did another chat, and they say you can only get energy monitoring through the Tapo app (it’s a bit unclear from their answer, but it sounded like they show up in matter but come through the app/cloud somehow).
It’s going back to Amazon.
See discussion for the P110M:
So it may be a firmware issue with Tapo? And because I didn’t use the app did not see it?
Their support told me quite clearly I had to use their app to get energy. I guess if their bot (sigh, I hate companies that make you talk to an AI) had language problems that could translate to “update the firmware with the app then pair with matter”, but it said pretty clearly that you then add to HA as another (not sure of the word here) in addition, like a link. Which I don’t want to do.
Don’t know, don’t care… if I can’t just run matter and install it, it’s going back to Amazon.
Heiman is a good counter-example, bought 5 of their smokes, and 2 of their CO detectors, they add to Matter with no other app, they update the firmware right from HA, and it just works. So it is possible.
When there’s a firmware update but it doesn’t show in HA, is that due to HA (nabu casa) not doing something, or due to the vendor not getting it in the channel correctly?
