I bought them a week ago and they lasted me about 3-4 days.
If I spend €2 every 4 days, then it costs me about €16 per month.
Other external cleaners I use last a whole month and cost me €4 per month.
Also, they have no scent.
I need to find another one that lasts a whole month, has a nice scent, and doesn't cost me more than €5.

It dissolved very quickly in water, lasted a total of 5 days. (no, I did not remove the transparency)

Whatever it does... it does... but it consumes (melts) very quickly... it does not last more than three days, and depending on the usage, it can last even less... another disadvantage is that it does not have a scent... the worst of all is that you cannot combine it with any other type of cleaner, e.g. wc duck or a chlorine-based one, it doesn't make sense... for occasional use, it is good... personally, I will look for something better and use this occasionally... for frequent use, although it is economical, it is not recommended!

It dissolves very quickly in water, resulting in it lasting less than 5-6 days for average use 6-8 times/day (proportionally for one person), and the density of the aromatic liquid in the water has already decreased significantly. While it lasts well, it seems too short for toilet use by one person. I would expect <3 weeks to say that it's worth its money (purchased from a supermarket at a price multiple times higher than that on Skroutz)