They worked just fine when I needed to try them on cables I cut to adapt them accordingly to my network. It gives you the ability to see that everything works well and you can rest assured that the job was done correctly.

I don't know if it will work, for example, next year, but since I got it (2 weeks ago now), it works just fine with all the cables I've tried (although I don't have many cables to test).
It worked correctly both with grounding and without. I haven't encountered a faulty cable yet to see what it would show.
For the money, though... go for it.

I had to fiddle with the connector to get it work.
Good job only needed it for the one job as I was supposed to be on holiday - in the bin now !

5 stars because for the money it does what it needs to do. For more serious uses, it is not as reliable

A simple typical Tester (it's now a kilogram but it does the job) for telephone cables with RJ11 and Ethernet RJ45 tested them all even shielded CAT 6 with grounded RJ45 clip all 8 LEDs and the Ground work for me. For its simple operation at 4~5 euros, it has definitely paid for itself; if you want something more durable for continuous intensive use (go for Uni-T at around 12 euros). It checks the cables for their functionality whether they are crimped by you or ready and you want to see that they work. It does not come with a battery in the package; it takes a flat 9V one.

Simple and easy to use.
I used it for mapping and checking the internal network of an apartment (concealed cables).
Also, for checking and troubleshooting old device connection cables.
It quickly recoups the cost of purchase.

It requires a common 9V battery and cables/adapters depending on the type of network and testing, which are not included.

If someone needs it to check 10~15 cables, it will work correctly. If we are talking about a larger number, the tester will encounter problems. Mine was giving wrong indications after 15 cables and I had to replace it.

Chinese quality. It works for now. Don't expect miracles at this price though, let's not kid ourselves.

Good, but if by mistake the other side of the cable is plugged into the telephone socket or the switch, there is a very good chance that it will burn.

It does its job well and reliably, for me who occasionally will make a cable or test structured wiring in a friend's house for troubleshooting.

For professional use. Cheap that you don't care if it breaks. I have bought 5 in total for everyday use in networks. And if it breaks and a light bulb burns out, you don't care.

Cheap Chinese stuff just enough to get the job done. I don't have an STP cable to check if the grounding LED is working.

It does its job, however it should not have control over the cable shielding as it claims. Other users who have opened it report that the corresponding LED is missing from the board...
Personally, I am not interested in shielding for the cable tests I do, so for 3 euros it is excellent!

As long as it worked, it was good. Suddenly one day when I needed it, it was dead. It didn't even make its money back, but it has good value for money. I will buy another one.

I agree with what has been written and I made corrections as I wrote about the weak LEDs. The LEDs were not to blame, but the "crappy" economy type battery. I changed the battery and the tester works great. Does anyone want anything more at this price? Not me, anyway.

It works without any problem and does the job it is intended for. However, the 9th LED for grounding control does not work - it does not even have an LED inside to indicate, nor contacts to measure. But for checking the 8 regular cables, it is fine.

It does its job just fine. No problem. It has a port for both telephone and network cable

It does the job it's supposed to. The second time I needed it, it still didn't work even after changing the battery.

Flawless for its job. I found rewire (wrong connections in the plugs) both in some cables I had fixed myself, as well as in ready-made fixes (!!!!). Tested on Cat5e.

While it claims to be able to test STP and FTP cables and has (supposedly) LEDs for grounding (G) check, there are no LEDs attached to G neither on the main device nor on the secondary one. So the only thing it can check is the 8 wires in the plug. Get it only if you don't care about grounding.