The Speedball Water-Soluble Block Printing Ink Extender mixes with your water-soluble block printing ink to create gorgeous, transparent colors.  Simply apply a small amount of ink to the extender and thoroughly mix to increase ink transparency.  The viscosity of your block printing ink will not be affected when using the ink extender, so you will produce consistent results every time.  Clean up is fast and easy.  When you are done with your project the extender and ink will wash off using soap and water.  The Speedball Water-Soluble Block Printing Ink Extender is ACMI AP Certified, so it is safe for everyone to use both at home and in the classroom.