This versatile mid-sized stamp pad features fast-drying, solvent-based pigment ink that works on a variety of surfaces including paper, glass, metal, shrink plastic, cellophane, aluminum foil, leather and acrylic. This ink does not react with watercolors or other water-based media, making it great for use in mixed-media projects. Acid-free and water soluble for easy clean up. The ink pad is 2.25x2.25 inches. Raised surface allows for inking up any size stamps!