Beautiful highly saturated acid-free transparent colors for your classroom or art project needs. They are alcohol-based making them indelible and moisture-resistant when dry. You can work freely on almost any clean surface including glass plastic metal paper and vinyl. Highly-versatile for a variety of applications: rubber stamping fine art wood and leather faux finishing techniques and airbrush. Set of nine 1/2 ounce (14 ml) bottles. Conforms to ASTM D-4236.