From the manufacturer:
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 letters, 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 alphabet-themed book includes every letter of the alphabet (uppercase and lowercase) to trace, alongside pictures of familiar objects to illustrate each sound. 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.