Clover White Marking Pen, Fine. Recommended for making marks on black or dark colored fabrics. White Marker ink disappears with use of iron or when washed. Caution: try the marker on scrap of same fabric before use; do not use the marker on non-washable fabric like silk. If the marker does not flow smoothly when you first begin to use it, rub the tip gently against a piece of paper or fabric until the ink flows easily. Marks will gradually begin to appear after 10-30 seconds. Marks may not be easy to see on coarse, napped, thick or light colored fabrics. You can retrace your marks if they are not easy to see on the first pass. If marks don't disappear with ironing, they can be removed by rinsing the fabric with water.