Daler-Rowney has made this Ox Gall Solution that is perfect for all watercolour artists out there. The solution comes in a 75ml bottle, and works by extending the use of your watercolours giving you a lot longer to paint for endless hours of creativity. It works by improving the wetting and increasing the flow of watercolour paints by simply adding a few drops to water. This make Ox Gall a self sufficient art tool that any watercolour artist should have. - Brand: Daler-Rowney - Size: 75ml - Ox Gall Solution - Ideal for extending the use of watercolours - Improves wetting and increases the flow of watercolour paints - Add a few drops to water before using