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 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 10quot x 625quot x 15quot