C.S. Osborne 12 Clay Based Marking Chalk - # 88
Box Contains: 8 White, 2 Yellow, 1 Red, 1 Blue.
Clay based and much easier to erase.
Other chalks that are not clay based will leave a grease on cotton and other fabrics.
Also wooks on glass and vinyl where other chalks don't work.
`Due to the shape of these chalks, a sharp marking edge is maintained
