Prang Hygieia Dustless Board Chalk; White - 12 Sticks per Pack; no. DIX31144
This superior chalk is 95% pure calcium carbonate and free of foreign materials that work their way into the board surface causing scratching, streaking and pitting. Round stick 3-1/4" x 3/8" fits most chalk chucks. Available in white, yellow, and assorted colors. AP certified non-toxic.