This is just one of Vamp eyeliners. Checking Pupa's website revealed a good collection of liquid and pen liners with different tips. This is their pen eyeliner with the medium thick applicator. I've tried my fair share of pen eyeliners before I landed on liquid formulas (Catrice). Pens are convenient, but at some point you get really annoyed by how fast the tips dry. I've tried Pupa's Vamp mascaras, which are great (regular black and coloured ones), but this eyeliner never managed to really convince me. 

I'm used to a very reliable Catrice's formula, with which I can draw a line on both eyes without having to dip the applicator into the formula between the applications. Pupa's is a fairly average felt tip pen eyeliner, at which I have to stop to shake it and try to saturate the tip again between the eye applications or even very occasionally during the single application because it loses colour quickly. It's also not as intensely pigmented as I expect from an eyeliner. You can do a nice application with it, it's just more time consuming and you may end up with a line that's thicker than you originally planned.