So, the product was used in a Mercedes C200 W203 with a very small leak in the heater radiator. The passenger's window would fog up slightly. As soon as the product was added, after one or two days of operation, the problem did not reappear. So far I am very satisfied.
It is a temporary solution until the repair is done, don't forget that.

Be very careful with this product and all similar ones.

What I managed to do with this product was to clog the entire system and cause the car to overheat, fearing that it might have blown a gasket due to the system being blocked, whether it's the thermostat, water pump, a blockage in the radiator, or the hoses - seals, etc.

Most mechanics do not recommend such crazy materials, I learned this afterwards.
Ask an experienced mechanic or someone who knows exactly how to use it.
The product should also list the dangers it may cause.

Be very careful!

12 hours after application .,, ! So far the product has done what it promised, it's just that the method of application is a bit strange. The bottle says, and according to what I read, the engine should be cold. I bought it to use in a 2004 Smart diesel. I just think that the mixture should be mixed first with the radiator water and then put into the radiator, the mixing should be done externally.

The reason is that I put it directly into the radiator as the instructions say, and as a result, because the mixture is very fluid, it couldn't get inside and the engine temperature instantly rose to 107 degrees. For 3 minutes!!

But yes, it does stop the leak

It stopped the leak I had in my fridge, it was constantly losing coolant and I was refilling it, I didn't expect it

I don't know if this specific product helped, but a leak I had from a gasket in a Seat Ibiza 1.0 6k1 no longer drips and is not losing coolant.

It did the job I didn't expect it to, applied 6 months ago for the refrigerator radiator, it stopped the small leak it had

It closes small leaks in the refrigerator. Read the instructions, the motor must be cold and the level must have dropped somewhat so that it reaches MIN-MAX when you put it in. And make sure to drive 10-20 km when you put it in so that it works properly. Check daily and top up the coolant, to see how it goes.

Increased temperature and water was thrown away... and before it was increasing but we hadn't reached that point...
We continue with side effects, the heater in the radiator doesn't work and the engine burns like water.
All instructions were followed to the letter.

I put the product in the car and the small leak that existed stopped, I relaxed because I was constantly checking if there was any liquid and I kept buying spare parts... anyone who has a problem and can't detect the small leak should get it

There was a coolant leak which was fully repaired in about two days of the car's operation

It works. I bought it because of a small leak to avoid the mechanic. I didn't believe it, but now it's been 6 months and I haven't seen a drop.

Every week I would put about 500 to 600 ml of water in the refrigerator. From the day I put it, I filled a shot glass after a week, and now after a month it took a tablespoon... very good...

Two days ago I tried the additive. So far, it's doing the job. It fixed a small visible leak on the side of the refrigerator. I had to refill 50-100ml per week before.
The area that was leaking is now dry. I will monitor it and update.
TIP. When using the additive, in order to prevent the radiator from clogging, the heating should be set to maximum (temperature and fan) for at least 20 minutes after the car has reached its operating temperature.

I put it in a refrigerator that was leaking water, and besides the refrigerator, I also had a leak in the thermostat. Everything stopped, it doesn't leak from anywhere for a year now. When you put it, it needs to work at idle and immediately after a good walk to work and circulate the water well. Do not put it without the car working and do not turn it off as I said, it needs a good walk.

I used it on a crack that we couldn't find in a JCB BNC Leyland machine, with caution, but it did its job, it doesn't leak at all, the question is how long it will last. I am satisfied with the product.

It was used in a VW Jetta with a tsi engine (BMW-140PS) for a leak that was very difficult to locate, as it only occurred when the engine was running, about 200ml per 300km. I followed the instructions exactly and fixed the leak immediately, but 3-4 months later, when winter came, I realized that the heater core had clogged and I didn't have hot air in the cabin, so it required flushing (where it removed the white liquid from inside).

I didn't believe it until I tried it. In a refrigerator that was losing refrigerant (0.2-1+ liter) per month, I haven't had to refill a single drop since I started using it a month ago! I am convinced that wherever the leak was, it has been sealed! I wasted money for so long on refrigerants, fearing the expenses of replacing the refrigerator... It says that it doesn't cause any long-term harm if it remains in the system, but I have my reservations too... Buy it without fear!!!

Edit 11/11/20 WARNING! It does indeed cause problems with the radiator and heat. It clogs the pipes. However, the leaks have stopped

Amazing product for small cracks in the cooling circuit. I put it in an Audi A4 1.8t, which used to require 1 liter of g12 every 5 days due to a crack in the radiator, and the leakage stopped immediately. It hasn't lost a single drop for the past 6 months.

My car had an unpleasant smell that wouldn't go away no matter what. I had tried everything. Finally, an electrician told me that there might have been a small leak in the refrigerator and the refrigerant was causing the smell. There was indeed a leak, as I had to refill the refrigerator every 2 months with about 750 ml. Finally, the problem was solved! Both the leak stopped and the smell! I didn't expect it to work!

Perfect, I had a leak in the radiator which meant removing the entire dashboard. I decided to try it and it worked immediately. It didn't cause any issues, didn't clog anything. I still have it in the cooling system (2 months now). For better or worse, I will change all the fluids because, after all, I don't like the idea of leaving a sealant permanently inside the system, even though it says on the box that it doesn't harm anything in the long run.