This Double Ended Marker with extra fine brush tip has acid free and non-toxic water based ink. The fine brush tip is large enough for direct use on rubber-stamps. Make multi-colored impressions by using two or more pens on the rubber before stamping. This conforms to ASTM D4236 standard and comes in carded packing. <li>Double ender marker with extra fine brush tip </li> <li> It has acid free and non-toxic water based ink </li> <li> This watercolor marker is the ideal pen for your art or rubber-stamping needs </li> <li> Make multi-colored impressions by using two or more pens on the rubber before stamping </li> <li> Available in over 60 colors; measures 1/2-inch length by 2-1/2-inch width by 9-1/3-inch height </li> <li> Perfect for Coloring Adult Color Books</li>We Recommend These Products: Uchida 1122-012A Le Plume II Double-Ended Markers, Fine Tip [https://www.ebay.com/itm/283523859305] (https://www.ebay.com/itm/283523859305) Marvy Fine Line Opaque Deco Paint Markers [https://www.ebay.com/itm/283523859235] (https://www.ebay.com/itm/283523859235)