Set of colour changing painting brushes.
A brush I made for more fun colours while painting, I would recommend using it after you've placed down your base colours and general shading so you can more easily work within the colour change.
Be mindful of the direction of the brush if you want the actual 'teeth' of the shape of show up, you might have to go over it several times (if you want the colour to be the same dont lift your pen) or just use the one that's without the blending! : )
Brushes