This is the 24 pen set from Jetpens, they are the Pilot Frixion Pens, that are not yet available in the US, but they should be. They are a bit pricy at $50 a set, but there is a bunch of ink in each, so they should last a good long while. I bought them about 7 months ago and I have been using them regularly since, and they are still going strong.
The colors are great, they are more pastel than bold, and the colors show up very well. They write wet, but surprisingly they do not bleed through no matter how thin the paper ( I have tested them even on thin rice paper) which makes them great for lots of things.
Naturally they erase well, and can be written over many times. I also have the highlighter version, and they are just as usefull, it’s good to be able to highlight and be able to erase it again if I choose the wrong color…