The Laundry-Tec is a highly wash resistant Hi-tecpoint rollerball specially designed for marking textiles. Great for labeling clothes but also for creative works on textile. 1.0mm medium needlepoint. Filled with quick drying alcohol type ink. Iron ink to encourage permanence. The ink is set by ironing for 1 minute (cotton setting). Designed for use on most fabrics, dries instantly and stays permanent throughout washing. Great for marking clothing, and school uniforms.