Hero Arts-Kelly Purkey Stamp & Die Set. These clear stamps peel off their backing and stick to any acrylic block making for easy stamping. Simply apply your favorite ink and stamp crisp clear images! They are made from 100% photo-polymer which is latex free, phthalate free, non-toxic and biodegradable. Use the die for an added layer! This package contains To Do List: a set of thirteen clear stamps on one 3x3 inch backing sheet and two dies. Made in USA.