Difficult to register and very poor quality login, if you see it looks very Chinese like some cheap bluetooth tracker from eBay. Practically, besides the map with the marker, nothing else worked. Maybe I didn't make the right settings, which were anyway very complicated. I gave up and didn't bother. I picked it up again recently to try again and the battery had died in 4 months as others mentioned (maybe even earlier). It's a shame because it had potential due to its size in the wallet, and in the end all I did was carry it around inactive for so long.

Quite good as it is thin and fits in wallets, small bags, etc., but the accompanying application is not integrated into any Google Home or something else, at least not yet...
The only downside is that its battery will definitely need replacement, maybe in less than 1 year.

It has already helped me twice so that I don't lose my wallet!! If the phone gets away from the wallet, an audible notification comes to whichever of the two devices you choose or even to both at the same time! If you forget the wallet, the phone notifies you, if you forget the phone, the transmitter you have placed inside the wallet notifies you!! Very good idea, at a very low price and with the guarantee of Baseus!! The only downside is that the battery will last about a year and cannot be replaced. Once the battery is finished, you simply recycle the device! However, the cost is so low that it doesn't create an issue even if you order one every year. It pays for itself and more! There is also a bigger sibling (T2) with a replaceable battery, but it costs quite a bit more and for now, someone can only find it in Chinese stores!

Update - November 2020

The battery, instead of the promised one year by the company, lasted only 4 months. Disappointing, even at such a low price.