Extend the use of your stamp. No toxic substances, no acid, no formaldehyde, and no heavy metals. Absorbs surrounding humidity to stay moist. Optimal grip for easy replacement. Designed to fit the printy 4927, 4927 typo, 4957, 4727 and 4727 typo, the pad will effortlessly fit into your self-inking stamp to continue the longevity of your impression. Environmentally conscience, the ink is water based so features no toxic substance, acid, formaldehyde or heavy metals.