<br>Features: <br> <br>Safe material: <br>The coloring books is made of average thickness paper and both sides are available, so you are suggested to use colored pencils, gel ink pens, chalks, crayons but not marker lest the back of page gets ruined. <br> <br>Enhance creativity： <br>This is a coloring book need your kids to color according to their own ideas, so it can greatly stimulate their creativity and imagination. It also a good gift for parents or teachers having coloring together with kids, a good opportunity to increase the relationship. <br> <br>Specifications: <br>Material: paper <br>Size: 5.9 x 3.9 inches <br> <br>Package includes: <br>30 x Graduation coloring filling books <br> <br>Notes: <br>You are suggested to use colored pencils, gel ink pens, chalks, crayons, but not marker lest the back of page gets ruined. <br>Manual measurement, please allow slight errors on size. <br>The colors may exist slight difference due to different screens.