Hero Arts-Kelly Purkey Cling Stamp. These Clings are repositionable stamps backed with a special material that uses static cling to stick securely to acrylic blocks for clean easy stamping. Each one is hand made with 100% all-natural rubber that is latex free, phthalate free, non-toxic and biodegradable. This package contains Background Squares: one cling rubber stamp on one 7x4-3/4 inch backing sheet. Made in USA.