**Feature** Nib Size : Mediun Package : 10 x Jinhao Spare Nibs and 1 x lanxivi pen pouch The ten spare nibs work with Jinhao 450 and Jinhao 159 fountain pen . For how to Replace the nib : One hand holds the barrel while other hand Grasps the nib ， then pulls the nib out with a little swing . After pulling the nib out ， just pushes the spare nib to its original position .