They are not the most beautiful pens, but they are great for teaching Physics. The others with the cat eye are more beautiful. However, these ones are more distinguishable

We ordered them for my little brother and although the receipt said "Gazes Volos Colored Set = 50 Pieces 16mm 116576", the contents of the package we received were a package with 10 volos of 16mm and one of them had a dimension of 25mm. The volos were not only fewer, but they were also transparent white and did not have a design inside. Therefore, not only did they send us a different product, but also a very simple - and probably in stock - version of it. We do not recommend it.