To replace the nib, grip the top of the old nib and the feed of your pen and unscrew the nib unit from the grip section. Grip the nib and the feed of the replacement nib unit and screw it into the grip section until it is tight. Do not grip the nib by its sides as this can damage the nib. Do not remove a nib from the feed. Removing the nib from the feed will void the pen's warranty.