ENDLESS POSSIBILITY: Shuttle Art 15 Vibrant Colors liquid chalk markers, reversible 3mm fine tip is perfect for crafting and DIY projects, used on any NON-POROUS surfaces such as menu boards cafe, pub and bistro menus, chalkboard labels, metal, car window, house Windows, glass, Mirrors, and much more. KIDS SAFE AND MESS FREE: Shuttle Art liquid chalk markers are washable, dustless, non-toxic. Conforms to ASTM-D4236. It’s time to replace the old dusty chalk with white chalk ink markers. COMES OFF EASY: The chalkboard pen will work on almost any surface. When you’re ready to write & start fresh, a mere wipe of a wet paper towel will remove your erasable chalk markers completely and easily from almost any NON-POROUS surface. Please NOTICE that the ink is PERMANENT on POROUS surfaces. MADE FOR EVERYONE: Eco-friendly material is great for kids and adults. Whether you're a Teacher, Mom, Student, Artist or Business, Office or Restaurant Owner, our liquid chalk ink markers make creating beautiful messages effortless. SERVICE GUARANTEE: Your satisfaction is our top priority, please rest assured to purchase our products. If you are not satisfied with our products or have any questions, please feel free to contact us at any time. PLEASE NOTICE: If your chalk markers do not flow well when you don't use them for a long time. Please take off the tip and clean it under straight water-flow; Then, using the dry cloth or towel to dry the tip; Last, install the tip and test. Shuttle Art 15 Vibrant Colors liquid chalk markers, reversible 3mm fine tip is perfect for crafting and DIY projects, used on any NON-POROUS surfaces such as menu boards cafe, pub and bistro menus, chalkboard labels, metal, car window, house Windows, glass, Mirrors, and much more. Please notice that if your chalk markers do not flow well when you don't use them for a long time.Please take off the tip and clean it under straight water-flow;then, using the dry cloth or towel to dry the tip; Last, install the tip and test.