First of all, they fold for better transportation even though it was not clear in the initial description and they are of excellent quality. However, the big advantage is the battery. You charge it once and that's it! On the downside, they heat up the ears after an hour of use.

Positive:
- Clear sound.
- Deep bass.
- Good battery life.
- Easy pairing (check the instructions before discarding them).
- Good plastic quality.

Negative:
- Low volume compared to other similar devices playing at 40% lower (for crazy people like me who want their drums to shake like a woofer).
- Ears sweat easily.
- Very short aux cable.

(The volume issue might be due to the PC's sound card) I don't know if others have the same issue.

Very good headphones especially when you look at the price,
- Excessive bass with the extra bass button (I don't mind, after all, that's why I bought them)
- Incredible battery, it's Anker after all! They came with 80% battery and after 5 days of use with at least 5 hours per day, they have reached 65%, so don't be afraid of the battery.
- Large cones that fit comfortably inside the ears, after many hours of use, the ears may start to sweat, especially if it's hot.
- In terms of music, they are for bassheads like me who listen to house, techno, trance, etc. They don't have amazing sound detail and I haven't tried an equalizer yet to see if I can improve things a bit.
- In gaming, I enjoyed every shot I fired with the extra bass!
- In terms of connectivity, I have connected it to my mobile phone and laptop and I have an issue with the connection to the laptop only, sometimes it loses connection, I don't know if it's the laptop or the headphones..
For this price, it's a very good choice and I recommend it if someone doesn't want to spend more than 40 euros (I bought them for 35 euros including shipping)
That's it! I will come back if I see something else!

VFM at 20 euros from outside. Very good bass, very good construction, perfect sound isolation.
Very satisfied.