This set includes four vehicle-themed activity and coloring board books, each with a refillable water pen. The reusable white pages display simple line drawings when dry and reveal colors when wet. The chunky-sized water pen is designed for easy filling and gripping, suitable for small hands. The books feature a compact, spiral-bound format, making them convenient for travel. This product supports the development of fine motor skills, early writing skills, and visual discrimination. It is made with FSC-certified materials (FSC C156584), ensuring responsible forestry practices—applies to new inventory only.