Uoline Chalk Markers can write on any non-porous surface, including chalk labels, mirrors, glass and even metal. Any SMOOTH and NON-POROUS Surfaces: Small Chalkboard, Whiteboards, Window Paint, Small Chalkboard, Framed Chalkboard, Chalkboard Stickers, Menu Boards, Bistro Boards, Chalkboard Sign, Chalkboard Paper, etc. Versatile:can be used as glass markers,window markers,chalk pens,colored chalk,chalkboard markers,chalkboard pens,blackboard markers,chalkboard paint Leave Messages Almost Anywhere with 8 Vibrant Liquid Markers and 8 Bonus Erasble Labels!!