Exception Silver boasts a complex chiseling process truly unique to Waterman Each pen receives 3 sets (BP) or 5 sets (FP) of 4 parallel lines that re engraved on the 4 sides of the pen. Each set has a different and unique length. Exceptions quadrangular shape makes this chiseling very difficult to obtain. It is a unique chiseling, breaking away from traditional vertical chiseling. The chiseling asymmetry marries with the symmetry of the square. This unique association gives new dynamics to the pen, in contrast with standard vertically chiseled pens in the market