I have had this tool for 2 years and what I have to say is that it never let me down! I always easily or difficultly found the pairs I wanted, either in racks and network sockets, or in OTE distributors in apartment buildings with the central sockets of the house.

By saying difficultly, I will tell you what I mean... There were times when I had to search for cables in literal mess and because there are still non-voIP lines, the machine would hit everywhere without being able to determine the pair!
So, by changing the frequencies from the generator (it has various options), in the end, you manage to hit the spot where you want.

It also has the ability to measure cables, e.g. from an RJ11 socket to a pair termination or an RJ45 socket to a rack, where with your tester it shows if there is a short circuit in the pairs, a cut cable, or if it's okay, as well as testing if the cables have been terminated correctly based on the wiring scheme you have followed (usually T568B, which we use).

Also, the detector has a small LED light on it (nothing special, just mentioning it), the ability to adjust the sound (in case you don't want it to hit loudly for some reason), and it can also accept headphones (so that it is not heard at all in the surrounding environment).

The only thing you should always keep in mind with such tools is to have spare batteries with you (if I remember correctly, it takes a 9V) because they do not warn you and in case of crazy indications, simply replace them.

I bought it in August 2019 and have used it very little, 4-5 times, a total of 20 cable measurements. The day before yesterday, while I was measuring cables, it stopped working and showed everything as short-circuited. No matter what I measure, it shows it as short-circuited. It is likely that the remote unit is broken. It is out of warranty, they say, only 1 year. There is no spare part, service only if they see it at the company and if... obviously with a charge... I sent an email to Proskit (Προτογαλία) and asked to buy the remote unit, it shouldn't cost more than 10€. I am waiting to see if they will respond. I will update on any developments.

I regret the 85€ I spent for it to stop working after 1.5 years with minimal use and of course without any drops, etc...

Update: After 2 months and 3 emails to Proskit trying to purchase the remote unit from there, there was no response at all!