Add a additional nib to your existing Elmo, Fortuna, Ducale and Harry Potter Pens.
Extra Fine, Fine, Medium, Broad, Stub 1.1 and Stub 1.5
Please note: To fit these nibs make sure you have the new style feed see image below. The convertor must be unscrewed before unscrewing the nib. Please see video demonstration by Peter Jesper below.