Also Great: A Gel Pen Set That Includes Metallic & Glittery Colors: Soucolor Gel Pens (60-Pack) Here are some of the best markers for adult coloring books — plus a set of gel pens with fun ...

Aen Art Gel Pens for Adult Coloring Books: available at Amazon Our take: This large assortment of colorful gel pens gives the artist in all of us a chance to shine.