- Markers for writing on the upper side of CDs, DVDs, Blu-ray discs, overhead transparencies, etc. ,- With permanent ink ,- Erasing pen for easily correcting mistakes , ,Note for Consumers: ,Moisten pen lightly if not used for a longer period before using it again. - Permanent: Yes ,- Line Thickness: 1 mm ,- Colour: Black/Blue/Red ,- With Erasing Pen: Yes 2 years legal warranty only