Non-permanent marker pens are different to permanent marker pens because they are designed to not have permanent ink, you can remove the ink either by wiping or erasing, which is great for creating signs and menus, where you may want to remove the lettering to be able to start fresh.
Spectrum Noir TriColour Aqua Markers - Colour Basics (Pack Of 3)
An excellent beginners kit including a selection of classic TriColour Aqua markers from Spectrum Noir.