Excellent soap.. It is NOT a pre-wash foam!! Don't confuse it.. There are many soaps, what separates the good ones is obviously the cleaning ability but also the lubrication so you don't scratch the surface.. And there it is excellent!! Koch chemie top products. Check out my channel on youtube
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Very good shampoo for light dirt and it makes a rich foam.
If the car is very dirty you should use a prewash first because due to the neutral pH it won't do the job unless you use some elbow grease..
When the car is very dirty I first use vb when it's very dirty but you need to be careful..
Then I use gsf and finally pw.
If it's just dust I go straight to gsf and that's it.
1 liter gives you many washes if you use the right amount..

I don't know what people consider clean in the comments that give five stars. With just a frother and no hand, it doesn't do anything different from a good shampoo. With a bucket, it's perfect. Together with the Green star as well. The darkness was on after two hands and a ratio first as it says and a much higher one for testing.

Guys, you buy it with your eyes closed. First of all, it cleans very well. A big positive is that it doesn't break the coatings on the car or the boat and gives an amazing shine. I will definitely buy it again

The product foam soap Gsf, the yellow one, was mixed at a ratio of 1 to 40 per liter. With the addition of the green star auxiliary at a ratio of 1 to 25. Sufficient ratio according to the usage instructions of the products. For persistent dirt from muddy water, it has no effect. You need a sponge. Otherwise, nothing happens. On the rims, it removes the blackness quite satisfactorily. I washed 2 cars and unfortunately, without scrubbing, it had no effect on the bodywork. My cars do not have a ceramic coating or wax. The dirt was difficult, I admit. The pressure washer is of medium power, 135 bar. The foam cannon from Parkside is cheap, but it produced foam relatively adequately. The foam lasted 5 minutes, but the result was rather unfortunate. As a shampoo, it works in combination with a mitt and sponge. That was my experience.

I had seen videos on YouTube and read quite a few reviews but I didn't believe it. You spray with a simple applicator, leave it for a while, and rinse without using a sponge. It's fantastic. I added two caps to 500ml of foam maker.

Very good products, I tried them for the first time, mixed in a 10-liter bucket of water, dosage with a measuring cup of 50 ml each,
There was a very good cleaning, it left nothing, they are excellent products

If there was an option for 6 stars, I would give them. Initially, it cleans very effectively, and if someone combines it with the Green Star from the same company, they will never need to touch a sponge again in their life. Also, not only does it clean, but it also polishes while providing hydrophobic properties. The best part? The one-liter bottle delivers 50 WASHES! 50! With the recommended dose of 20 ml per liter. Koch Chemie - Guarantee

After 2 years working with an American product, this one won me over! Cleans, foams, shines! Perfect!!!

Magical. Combined with GS during washing (with a foam gun) and drying, it makes the cloth glide infinitely

It does exactly what it says!!! It cleaned mud from a 4x4 that was 10-15 days old without sponges or scrubbing. I will definitely buy it again

It doesn't make crazy foam, but we're not looking for special effects. It does the job 100% and without scrubbing.

Very nice fragrance. It does what it promises. Note that with its neutral pH, it does not remove tough stains or wax. It creates a very good and thick foam. I highly recommend it.

4 stars because it didn't produce enough foam for me even though I used 100 ml of Karcher GSF foam booster in a 500 ml foam sprayer. It may be the fault of the foam sprayer. Nevertheless, it is good with an incredible scent.

First use yesterday, after trying out foams from other companies.
Without adding Gs, which will be done soon, it was the first time that during car washing (dark gray color), even though it had been unwashed for over 30 days, having been exposed to rain and mud, I did NOT need to wash with a glove, meaning I only did a pre-wash and the car was completely clean.
Only observation, the car has wax on it and a pre-wash material was applied on the bumpers and wheels.
The conclusion I draw is that with some protection on the bodywork, either wax or even better ceramic coating, washing with a product like Gsf becomes a much easier and faster process.

Very good product with great dilution. With the foam gun, it doesn't give me a very thick foam, but the pre-wash seems to work properly. You can go over 50 ml per liter of dilution if you want to achieve better foam, but I believe it's not necessary. I also liked it a lot as a shampoo for hand washing, with just 2-3 caps it creates a very rich foam and good lubrication. I also bought the Green Star in case I want to enhance it.

I use it with a foam gun and pressure washer. It makes excellent foam and does not cause any problems with plastics. It smells nice and leaves a shine for days. It can be used together with GS for better results. It requires a very small amount and is worth its money, despite appearing expensive for its quantity.

It is very powerful, creates rich foam, cleans stubborn dirt BUT be careful with dilution. I put 30ml in 500ml of my Nilfisk foam sprayer that I use and it whitened all the black-unpainted plastics of my scooter that were in perfect condition, without being able to restore them to their original state.

Very good cleaning! First wash with this and the car had dried mud rain on it and it removed everything while before I used the autoglym pollar blast and it didn't remove anything! I put 50ml in a Karcher foam cannon and 450ml of water and it produced a lot of foam easily, it can even take 30ml! I put 30ml in a 5-liter bucket for washing and it was excessive, so 15-20ml does a good job

It's perfect... Cleans very well and leaves a perfect shine on the car... I mainly use it with a foam sprayer but also with a sponge... Perfect...
I should clarify that I use it together with the Gs from the same company.

It is possibly the best soap for the car. It is 7.5 pH and if you want more power, no problem. Add gs as well. It is made to be fully compatible!

The gentlest cleaner with neutral pH 7.5, economical due to high dilution, and effective. It does not remove wax or other body protectants. If you add green star, which is alkaline with pH 12.5, it becomes a stronger/alkaline cleaner equivalent to active foam with pH 9.5. If there is no protection on the body, there is super foam with pH 12 that removes everything. With two products, you can clean the interior, exterior, engine, windows, and remove salt residue from hard water. If using a foam gun, try not to rinse the body first, but use it directly and leave it for 3-4 minutes before rinsing

In the instructions it says 20 ml in 1 liter of water. I tried it for the first time and I was skeptical about the dosage, mainly because I have the cheap nilfisk foam gun, so I put 30 ml in 500 ml. It produced such a rich foam that easily covered the entire car (small) and I even had half of it left over. Needless to say, three-quarters of the work was done with the pre-wash. During rinsing, it was a bit stubborn to remove, which means that I did indeed use a lot of product. I used the remaining amount as shampoo (as specified in the specifications). In short, it's definitely worth it.