This Ecoline Brush Pen Set of 10 Grey Tones contains transparent watercolour pens which are perfect for drawing and illustration. The pens are filled with transparent dye ink and gum arabic which can be combined with watercolours. Great for digital artwork thanks to their consistent vibrant colours. Ideal for use with card, paper, watercolour paper and board. You can thin the ink to create colourful washes. The colours are not waterproof so they can be re-worked once they've dried. The 5mm brush nib allows for a range of mark making by applying different pressures. Odourless and fast drying, perfect for on the go painting. Not particularly light-fast, Ecoline advise keeping artwork in a portfolio for best colour retention.   Colours Included Cold Grey Light Warm Grey Light Grey Warm Grey Cold Grey Indigo Deep Grey Sepia Deep Black Grey