The picture above shows the different size Posca Pens available. The nib is pictured with each pen describing the approximate line the pen will draw in one stroke. The number of colours available changes for each category and is written in red. Pigments in the colours remain constant throughout the Posca range. So, dark blue in an Extra Fine will be the same as dark blue in a Broad Chisel. The largest Posca is shown here as 16cm long and should give you an idea of all the other pen sizes by comparison.