Easy to use!! Be careful, you need to soak it in hot water and then dry it with a hairdryer. The downside regarding the price is that it does not include even tape to stick it on.

Excellent price for this kind of product. Setup is a bit of a faff as you have to soak them in hot water and then let them expand and dry but it's worth it for the amount of money you save. I glued them to a big sheets of cardboard and now I have mobile absorption walls. Very very handy if you don't want to mess up the walls of your temporary studio space.

For their installation, I followed the "recommended method," meaning I soaked them in hot water and then dried them with a hairdryer (they reached 5cm). They didn't dry completely, so I left them under the air conditioner in the heat for 1 to 2 days. I tried to stick them to the wall with 5 stickers on each piece, pressing them firmly (as instructed), and 20 seconds later, at most, one would fall off the wall. I thought maybe there was still water, so I left them under the air conditioner again, dried them with the hairdryer, and added my own strong double-sided tape to the wall. The result was that they held for 2 minutes before falling again. It will probably need liquid super glue over each sticker to hold them... I hope whoever buys them puts liquid glue directly between the soundproofing and their stickers to avoid further hassle. After applying the glue, there has been no issue, and for 2 weeks now, they haven't fallen off the wall.

Very good product but it takes quite a bit of time and effort to get it to the condition it should be. (It needs warm air to reach the normal dimensions.)

Excellent product. It does exactly the job it is intended for. We used them as internal lining in a cabinet that contains professional equipment which produces very loud noise (to the extent that it could be heard on the floor below). Now you can't hear anything.

It should be noted that the panels come in compressed form and require heat to achieve their final volume. The package includes relevant instructions. We used a hairdryer and it worked perfectly, as shown in the photo. However, it does require a bit of patience.

The product is okay, but the specifications are misleading as the thickness is 2.5 centimeters and not 5. On temu, they offer exactly the same ones at half the price, but due to the smaller thickness (2.5 centimeters) I preferred to get those that, as the description stated, were 5. There is no reason to pay extra for better quality and in the end it is not actually better.

Very inconvenient to unpack and get them to the right size. Otherwise, they are what you would expect, just sound absorption panels. Note: if you want to do a proper job, you may need to buy a second pack as 24 pieces are not enough (even for a small room). Unless you want them for targeted use, such as covering a door, in which case 24 pieces are sufficient.

I bought this material for soundproofing a room. I put it on all the walls and the result is undeniably excellent. Really a huge difference. You enter the room and the whole sound changes exactly like in a professional studio. The only difficult part was to "inflate" them as they come compressed for obvious reasons. I just put 5 at a time in the oven at 70 degrees with the fan. Undeniably excellent product. I used spray contact adhesive for gluing. Installation was very easy. Those who say otherwise are probably doing something very wrong.
EDIT: One year later, the only advice I have to give is to make an X and a square with the contact adhesive because to save 10-20€, some pieces fell off but nothing to worry about. I am still extremely satisfied

A value for money package, ideal for anyone in need of this extra insulation. They are easily restored with the hairdryer, I didn't even bother with the other methods suggested by the manufacturer. Also, because I see that many people struggle with installation, from personal experience not only with these specific ones but also with other soundproofing panels, I would like to say that the best way to install them is with spray adhesive, with a good application on the entire surface of the panel so that it sticks properly and doesn't come off - which, if it happens, can be easily fixed with a simple spray application.

The panels help with the sound quite a bit, and they look nice on the wall.
On the negative side, there are a few things:
1) It takes a lot of work to soak them in water and dry them in order for them to return to their original size. I couldn't dry them with a hairdryer. They needed exposure to the sun for several hours.
2) They don't stick easily. I have tried various double-sided adhesives, tapes, and sprays. The only ones that held were a magnetic benzine glue spray (https://www.skroutz.gr/s/35796950/15133-%CE%A3%CF%80%CF%81%CE%AD%CE%B9-%CE%92%CE%B5%CE%BD%CE%B6%CE%B9%CE%BD%CF%8C%CE%BA%CE%BF%CE%BB%CE%BB%CE%B1%CF%82-500ml.html?from=catspan) and polyurethane for sound-absorbing panels.

I am not satisfied at all with this purchase...

Based on the reviews, I decided to get them!
I live in an apartment building...
I installed them on a wooden hollow door and they really didn't cut anything from my own sound or from the outside!! ...

I am very disappointed!!!

Very good soundproofing/absorption. And I found a cheap package/I am very satisfied, and I will buy again from the same store!

Very good soundproofing. The box contains instructions on how to restore the panels to their original form after they come in an airtight packaging.

The difference with and without them is immediately noticeable.

As for their placement, I used wallpaper glue in spray form.

Everything is perfect!

They arrived very quickly, I can't say that, the problems start with the stickers inside, they don't work at all, we got some more but nothing, we tried to stick them 3 times without success, they came off on the same day, that's it.

Very good product and it does its job, in a large enough quantity to fully cover a typical door and leave you with some left over. I have used it internally on a wooden hollow door and it has completely cut off sound from my own source, but it also works externally. It cuts off many frequencies and sweetens the ones it doesn't cut off enough.

This former one is worth its money to me, it has left me satisfied, I have it for three months now.

Performance for the price. I don't have suitable equipment to measure the difference in absorption between high and low frequencies. But you can tell the difference. It also depends on the percentage of room coverage.

Very practical product for anyone who wants good sound insulation, especially for those of us who want the sound inside the house to play loudly (music, television). Satisfied with my purchase.

Lightweight, flexible, beautiful, and above all effective soundproof panels! Ideal for radio studios but also for home rooms where one wants to enjoy their chosen music without disturbing or being disturbed. The adhesive included in the package is not very strong (perhaps to prevent damage to the wall color if we want to remove them), but there are other adhesives available in the market for this job, such as this one here: https://www.skroutz.gr/s/26542870/Minos-Spray-Adhesive-Spray-Minos-400ml.html?from=catspan

I am a professional musician, specifically a brass wind player (horn), and I need a practice space at home (so as not to wake up my child) but at the same time, I enjoy watching my favorite movies. They do a great job in sound absorption and reduce noise levels by 20-30 db depending on the frequency and intensity. It takes a little patience for them to inflate (I used a hairdryer according to the instructions) and they attach very easily with spray adhesive. Now I am getting additional pieces to cover all the walls (it plays a crucial role in soundproofing) so that there are no cracks through which sound can "pass"!

Incredible difference in sound quality. I recommend it for people who want to start singing professionally.

The product does the job indeed. I applied it on the door of the room, but also on various points of the wall and the sound inside stopped having the reflection and the quality improved noticeably as the echo ceased to exist.
Of course, the sound that comes out towards the outside, in the other rooms when I listen to music, was significantly reduced, mainly the treble.
As for the stickers, they stick as long as the wall is smooth or the surface is smooth.
If it is rough, it needs liquid glue or spray that sticks permanently.
To avoid damaging the wall, I stuck them on cardboard and then I glued the cardboard to the wall in just 4 points.
;)

Very easy to use, it cuts easily with scissors and you can stick it in various ways. The size of the squares is convenient. It provides good sound insulation, although I have it in a very small area.