Artline 841 Dual Nib Markers have the brightest ink to ensure that anything you write stands out and pops out of the Board. Suitable for use on DVDs & CDs do not damage data saved on disc. Artline 841 markers offer a fun and contemporary design with leading functionality.it is highly recommended to use a high-performance Artline marker. The Artline Permanent Markers an ergonomic shape,Dual Nib,smooth and gleaming barrel design for comfortable grip. This Black Colour Markers feature a 1.0 mm and Fine 0.4mm nib for smooth flow from the beginning to the end.