Uchida Bistro Chalk Markers are great to use on chalk board, dry erase boards, light boards, windows and windshields. The opaque, waterbased, pigmented formula is erasable with a damp cloth. You can make an eye catching display with these beautiful colors, or choose fluorescent colors and watch them glow under an ultra violet light. Store in a horizontal position when not in use and make sure cap snaps on securely. Bulk White- 6mm bullet tip.