Liquitex Paint Markers are professional-quality water-based acrylic markers that contain artist-grade pigments.
You can use them on a huge range of surfaces, including wood, card, metal, glass and primed canvas, indoors and out, and they are permanent and lightfast.
Both markers have a versatile chisel tip, which you can use to produce a whole range of line widths from 2mm up to the full 15mm, so they are equally good for sketching and for filling in blocks of solid colour.
They give you an even flow of paint due to their pump valve system.
Download a colour chart here