It is not as strong as I read in the comments.
Also, it does not need to be diluted for tough stains.

Wonderful product, it cleaned dirt that was difficult and made my bathroom tiles look new, and the grout as well

Effective, but it works better with a hand brush for scrubbing. It was also tested on grout and was effective there as well. It is very caustic, gloves, a mask, and protective goggles are needed.

Good but not so miraculous. I didn't even have such a serious problem as I see in the posts. I don't know what I might have done wrong. I think it removes dirt in some spots but it's not what I read about. Nevertheless, compared to a simple cleaning soap, yes, it does do a job and I will continue to use it in areas where a problem might arise.

Excellent product! I will definitely buy it again!

It worked on the joints. On the tiles, I wouldn't say so. I expected it to be more effective based on the reviews I read. It is very caustic. Be careful not to get it on skin or eyes, but also make sure it doesn't damage any surfaces

Incredible result on joints and tiles. If you have limescale that has built up over several years in a spot, pour the product directly onto the surface for a better and faster result

It does what it promises, but if you have very tough stains like I do, it requires many uses and a lot of scrubbing

It does what it promises. When you spray it on the joints it foams, and if you leave it for 10-15 minutes and then scrub the joints, it works wonders. It works better on light-colored joints and glossy tiles.
Attention!!! It is a caustic liquid. You must wear special goggles and gloves. Apply it in open spaces with open windows. If possible, wear a special mask as well, even better. If a drop gets in your eye, you'll regret it. It also affects the skin on your hands. You must wear gloves.
I took a broom handle and tied a scotch brite to it and scrubbed the tiles and joints from a distance.

Incredible product, it removed 25 years' worth of balcony grime that had never been cleaned from limescale, rust, and who knows what else. I poured it undiluted on the tiles and within 10 seconds it foamed up and removed the dirt with minimal scrubbing

F A N T A S T I C !!!!!
PERFECT !!!!!

It does the job especially on the joints, but to get the spectacular result you see in the before/after photos posted by those who used it, you will need to scrub...
A LOT of scrubbing!

Buy it with your eyes closed. It cleaned marks from flower pots, rust from the gas bottle in just a few minutes. Marks that had been there for over a decade. Spray on a dry surface, leave for 2-3 minutes, scrub lightly and rinse with water. Yes, 2-3 minutes are enough. It is the best

Perfect product... it removed stubborn stains from tiles and fully restored the grout on the balcony. You need to be careful when applying it, it is particularly caustic.

I used vinegar for years on the joints and they never got perfectly clean, they were okay but required a lot of scrubbing and it was a hassle.
I saw this in a video and thought I’d buy it to try it out, the 3€ was worth it.
I’ve also attached a photo for you to compare, guys, amazing job!!
Of course, it needs to be diluted, it says 30% on the back, you can eyeball it if needed.
I will definitely buy it again in the future!

As soon as I poured it on the balcony, the joints started to foam, it even removed stains from marble where primer varnish had fallen and wouldn't come off. With a little scrubbing, it removed dirt, stubborn stains from grilling. I recommend it.

On one side you see the dirty grout and on the other the clean one.

The conclusions are yours. No scrubbing was even needed.

I am SHOCKED! Unbelievable product. It cleaned hard dirt on a 20-year-old veranda. I had tried many methods, like scrubbing with wire, using a pressure washer, but nothing worked. With this product, I was shocked; in two minutes it acted and with very little effort and light scrubbing, everything was gone. The images show a part of the before and after. I highly recommend it

Easily eliminated rust from tiles!
Very good choice combined with its low price. I recommend it!

Easy to use and effective. Cleans dirt and rust from tiles. This is the second time I am getting it.

There are no words!! I got it after seeing the comments and the result was amazing! Get it with your eyes closed!

A whirlwind, cleans where all the others struggle. Finally, after many trials with various products, I found the right one for the joints and tiles of the terrace.

In 2 words...DOES NOT EXIST...
I’m trying to upload a video but I can’t..!!
I just poured it as it was undiluted, on hard water stains, salts, mud, and stains from pots...and it simply disappeared, no scrubbing or anything, just a simple wipe with the sponge and done, brand new!!!!!!

It cleaned decades-old stains, incredible product and indeed without much scrubbing. With a broom, you practically spread it, go over it with plenty of water 2-3 times with a mop, do a regular cleaning with detergent at the end, and you have a new floor. I tried it on marble too and it eats it away, so be careful. Of course, I went over all the marbles, it whitened them a lot, and then I scrubbed them with a sander and applied a duro stick sealant, and they became almost new. Amazing product.

Very effective on tiles, removed residues from pots and rust without corroding them. Be careful with the instructions, it is caustic

It does the job it promises. My terrace tiles had accumulated salts and dirt (from pots) for 15 years, it made them look like new in 5 minutes.

It does what it promises, it completely removes stains from construction materials after a heavy renovation, and I saved both inside the house and on the balcony! I always have one in the cupboard now for tough stains!

In an indoor tile, it is as dirty as it appears in the photo, it did NOTHING. It was installed without dilution for a few minutes and then scrubbed with a hard brush and NOTHING. It's like it was washed with plain water.

I cleaned balconies that face the main road and constantly fill with dust, and it didn't give me any trouble at all. It just requires attention to price and liters in the packaging