I bought these for my teenage daughter who was complaining about having to use pen in class but not being able to erase her mistakes. My friend told me about these so I took a chance. Holy cow am I glad that I did! I bought these and the Frixion gel sticks, which i gave to her because they were cheaper. We tested out a few of them and sure enough they really do erase. The black looks more like gray but that's the only thing I can find to complain about so far. Now I go around and show off my really cool pens that actually erase.