The pen nib was rinsed off with warm water and it appears to have had black ink in the cartridge at some time. We will leave the cartridge in the pen for an ordering reference.
After several searches we believe this is a 1990's Diplomat Attache' model Fountain pen with what looks like a stainless steel nib. The nib is marked " DIPLOMAT " with an " M " below and has decorative engraving on the nib face. The cap jewel has under the clear cover " DIPLOMAT " with their 3 line logo and " Germany " below this. The exterior has a matte dark blue finish and the threaded parts are not stripped they fit snuggly when screwed together. The cap snaps tightly onto the pen. The clip has a section with three bars incorporated into it.That is what clued us into it being the model we have listed. We do not have a full ink cartridge to test the writing but we were able to smoothly write with the watery ink when cleaning the pen. As with all used items it may need cleaning and some work prior to regular use. We cannot guarantee the writing quality of a pen we can not test.