The Craftdoodle Aqua Brush Pen is a travel-friendly tool for artists out there. It has a water reservoir in which you can put in water and keeps your brush moist! :) Just twist the barrel to open, and fill it with water, start getting pigment from your watercolor palette and start painting on the go! ;)
Each set contains 3 brush tip sizes- small, medium and large. It can contain ~5mL of water.