HERO ARTS-Cling Rubber Stamps. Hero Arts Cling Rubber Stamps are made with genuine all-natural rubber and a hand-cut premium 'cling' backing. They feature the deepest etch for precise impressions and will always cling to your acrylic blocks. This package contains one 5-3/4x4-1/2 inch stamp. Available in a variety of designs: each sold separately. Made in USA.