Zig markers are double-ended, with two chisel nibs for calligraphy and lettering. Available in 24 colors (see pictured color chart). Large nib is 5.0mm and the small nib is 2.0mm. The ink has archival quality lightfastness and is photo safe. It is water-based and will not bleed. Store horizontally to prevent dryness in one end. We are having a difficulty stocking this item.