Hero Arts Color Layering Butterflies Clear Stamp Set (CL867) This set is part of the Color Layering Collection. Look for a guide on the back for how to use these stamps Hero Arts Clear Design sets are premium-quality, USA-made photopolymer designed for true stamping impressions Tear-resistant, easy to clean, always cling, and non-toxic Use with an acrylic block for easy stamping Clean easily with Hero Arts Ultra Clean Stamp Cleaner