The pens work like a real paintbrush, they will not bleed and the soft nylon tips will not fray. The soft nylon brush tips have individual strands. They are pre-filled with vibrant watercolour paint. The set comes with a refillable water blending brush and a convenient carry box, perfect for traveling or art on the go. They are long lasting and can be used for multiple projects over a long period of time. If they start to feel a bit dry, just hold them upside down for 10 seconds, wet the tip, and draw.