As you can see it is not a felt tip liner but more of a brush liner if that makes sense. This makes it easier to apply thin lines and fine details.
The color is a nice deep black, I didn't do swatches on camera in the video but you can see on my eyes that it's really black. I didn't have to go over lines multiple times to make them opaque, one pass was enough.
One small things that I do want to mention is that it bleeds a little bit when working slowly with it. I am a bit slow because I am used to working with gel eyeliner that doesn't bleed. So I have to try and learn myself this new way of applying eyeliner.
I do think it is a great product, and I will keep you all informed on how long it lasts etc, because it is a nearly 20€ eyeliner. If you have any questions about it, be sure to ask in the comments, and you will see a better review on the product once I've used it more.