Made by gypsum material, safe chalkboard chalks are for use and great for most surfaces, such as white board, chalkboard and more. The ergonomically designed chalk body is convenient for you to grasp and use, suitable for home, school, office and more. Features -Color:Assorted Color -Material:Gypsum -Size:7.50X1.00X1.00cm/2.95X0.39X0.39in -Size:11.00X5.50X3.00cm/4.32X2.16X1.18in -Size:9.50X1.80X1.80cm/3.73X0.71X0.71in -Note: Random Color of the Accessory - The dustless chalk produces less, safe for use by children and adults, and making it easier to clean up after use. - Abundant quantity dustless chalks, enough to meet your daily and replacement use, can also share with others. - The included chalk holders avoid the child put the chalks in the mouth, and very convenient for adults to use. - Dustless chalk is made of reliable gypsum, prevents the chalk from breaking or crumbling, which can also reduce dust. - The chalk set come in bright colors, making it perfect for art projects, school, and other applications. Package list: 2 x boxes of Dustless Chalks 2 x Chalk Holders 1 x Eraser