Simply the best dye-based ink pad available. Acid-free and fade resistant for archival use. Fast drying, water resistant ink won?t smudge with markers or watercolor paints. Permanent on all coated and bond papers, resists bleeding and fading. Premium raised felt pad for use with any size stamp. Non-toxic. Conforms to ASTM-D4236. Pad Surface Size 2-1/4? x 3-1/2?