Super convenient for artists on the go, self-moistening water brushes are just paintbrushes with a water reservoir in the shaft: you simply fill up a water brush and get to work. Water brushes are perfect for aquarelle-style painting in watercolor or aquatint. They can be used with watercolor pens and pencils, or with powdered or solid pigment to avoid the mess and hassle of extra tools. They are also a must-have addition to any pocket watercolor kit for plein air painting. Browse our roundup below to find the best brush for you.