SAF Aranet4 Home: Wireless Indoor Air Quality Monitor for Office or School (CO2, Temperature, Humidity and More) Portable, Battery Powered, E-Ink Screen, App for Configuration & Data History

I've had it for a little over a year and a half. Really love it. From just checking the CO2 in my bedroom, to checking the CO2 in my greenhouse, it's a really practical gadget for anyone living/working in enclosed spaces.App is great, and viewing historical data is a breeze. Just wish it had wifi functionality for remote viewing when not at home, but I'm sure it would add to the cost of the device, and it would probably drain the better a lot quicker.My only gripe is that, with humidity levels above 50%, the numbers don't match with my other T&H meters, which include top brands in the market (names excluded as Amazon does not allow mentioning of other brands in a review). I emailed Aranet about it, to which they simply replied, "our sensor is more accurate." So, I guess I just have to average out the difference since I trust both Aranet and the competition. The truth lies somewhere in between lol

Top notch, European company, thankfully all units only in metric so it's not an issue. This is pricey but that guarantees the quality of what you're buying, and when it comes to testing the air you breathe and ensuring it is of the highest quality then you pay for what's needed.Some of the stickers are great to translate the CO2 levels to what that means; I wish a mounting peg came automatically in the package so it makes it easier to grab and go; it stands well anywhere and I'll see if there's a command hook that can be used anywhere to mount it easy.Your first line of defence is knowledge, and this will let you know if you are safe from poor air circulation and therefore airborne disease and other problems.

Love the Aranet4 CO2 monitor, but it is a bit pricy. It is super accurate, and the mobile app is top-notch. At first, I tried cheaper ones from Aliexpress, but they are just junk; their detection level was often at 2000 ppm, not sure what it is detecting, me and my wife were freaking out, and we had none of the symptoms we should have. After receiving Aranet4, it showed at 700 ppm range, which we felt was safer, and trusted the readings. It also fluctuated up and down to normal whenever we used our gas stove. Unlike the Aliexpress junk, it constantly stays high all the time.

This is afantasic little device that works well. It shows us just how much bad air is in the room, and we then open the doors and/or windows to balance it out. Lasts a long time without having to change battery. Display quality is great and easy to read, and bright enough to see in daylight.

As someone who has evidently been suffering from extremely elevated CO2 levels for about 10 years (Yes, it was horrible and I didn't know), I have to say this is a great product and has literally saved my health and well being. From what I know this product is essentially a top of the line air monitor but it comes with a pretty hefty price. While I love this product I must also include that I originally started with a much much cheaper air monitor (Qingping) which after a couple months of using them in tandem, seems to be consistently within 50ppms of the Aranet. I do not regret the purchase of the Aranet because it has more sophisticated sensors and takes readings in a fundamentally unique when compared to my Qingping which gives me added confidence in the results. I have never felt better thanks to my new ventilation fan providing me fresh air throughout the day. I literally would have never been able to resolve this issue without the use of these air monitors. For me, they were worth every penny. My only complaint with the Aranet is the physical monitor itself doesn't seem to be able to display temperature in Fahrenheit instead ofcelsius, but that's not why i bought this monitor. Great product. Hope this helps.

Eye opening to realize how some rooms build up too much CO2 - especially smaller rooms. Great in helping me investigate and figure out how to improve air flow / air movement / interchange to kids room.

Every thing works as advertised on Aranet model O9C58 . Co2 tested against Inkbird monitor both within 20 ppm or less of each other. Order arrived next day. Display is bigger on Inkbird.

I think, this is an excellent monitor. The app is also easy to use and reliable. I have never seen either the device and the app to fail after few months of usage.