This exciting activity book includes four reusable pages and a refillable water pen. Use the pen to fill in each activity, from coloring in boxes to tracing numbers, and see hidden colors and pictures appear with every stroke! Then simply let the page dry to erase the pictures and fill it in again and again. This number-themed book includes numbers from 1 to 20 to trace, alongside corresponding pictures of familiar objects to count. There are empty lines for practice, too! The chunky-sized water pen is easy for kids to hold and stores neatly right in the front cover. Dimensions: 10" x 6.25" x 1.5" Recommended Ages: 3+ years Conforms to ASTM D-4236.