We keep a small quantity of type 060 fountain pen nibs in stock, which are size 5 but are slightly shorter than type 180. They fit into Karas K series pens, Messenger, various Kaweco models, Loclen and many others.
They are not available in a kit compatible housing but the geometry and thread of the Bock housing is identical to type 180, therefore makers of custom pens, or so called kitless pens are able to use the same thread taps if they wish to make a fountain pen with a shorter size 5 nib than a standard type 180.
