In the year 1929 Pelikan was the first company in the world to introduce the differentiated piston mechanism. This technique causes the spindle inside the fountain pen to turn quicker than the end piece of the barrel, with the help of two different threads. To this date, this fountain pen exists in many different variations, and though it has been developed in design and technical details over time, the basic mechanism remains the same. Equipped with a differential piston-filling mechanism Piston filler including a 24 carat gold plating and an elaborately striped body made of celluloid acetate The nib of the Souvern piston filler M800 is made of 18 carat/750 gold Nibs are refined with a rhodium decor and their writing qualities were tested by hand Colors: Red Stripe, Green Stripe, Blue Stripe, Black, Burnt Orange(Special Edition), Grand Place(Limited Edition)