18kt solid gold #6 size nib and feed unit that can be used to replace Edison production model fountain pens such as the Collier Hudson Beaumont and Herald Styles. This silver-colored version is plated with Rhodium to give the appearance of silver to match the silver trim on certain pen color models. To Replace put your thumb and forefinger on the nib and gently unscrew the currently installed nib counter-clockwise until fully removed from the pen's front section housing. Then install the new nib by screwing clockwise into the section until the nib is firmly in place. Then connect converter or ink cartridge to fill up your pen and start writing!