Use extra fine point Bistro Chalk Markers on chalkboards, light boards, windows, windshields, and most non-porous surfaces. A wonderful way to create chalkboard art to attract attention and increase sales. They are opaque, water based, pigmented, and erasable with a damp cloth. Each pack includes 4 markers: fluorescent pink, fluorescent blue, fluorescent green, and fluorescent yellow. Sold as 2 sets for a total of 8 markers. This product ships in approximately 1 days