From the manufacturer:
These fabulous pens contain A specially formulated ink that stays wet on paper, providing the tack needed to attract and retain embossing powders until they are cured with heat. These pens are perfect for Scrapbooking, rubber stamping, paper crafting, and even Altered arts! Great for resist inking and watermarks also! This package contains two Ranger Inkssentials Embossing Pens, (1) each: clear and black. Acid free, bullet tip. Made in USA.