4 markers in each set, 3 sets included. Dry-erase markers contain specially formulated low-odor, dry-erase ink. They are perfect for classrooms, small offices and homes. They can be used on most whiteboards, glass and nonporous surfaces. Dry-erase markers with chisel point deliver consistent color quality for bold colors and great erasability. They are certified AP nontoxic and conform to ASTM D-4236.