These are my go to pens for vibrant strong colour and all my art students love them. They work just like watercolour paints and blend effortlessly.  The fine tip is perfect for line work and the second tip is highly flexible, like a brush.  These water-based ink pens can be used as watercolours, they are blendable, odourless, acid free and non bleed.  Perfect  for arts and craft, card making, rubberstamping, scrapbooking... the sky is the limit.