Write, erase, rewrite. Unique thermo-sensitive ink formula disappears with erasing friction or heat. You can use the included eraser on paper patterns and documents or use the heat of your iron to erase marks on fabrics. They're perfect for marking quilt piecing or applique outlines and tracing patterns on a variety of fabrics. Inks are bold and easy to see on a wide array of surfaces with pens coming in a variety of colors, so pick up your favorites!