The Montblanc Meisterstück No. 25 in coral red was produced in Denmark between the 1930s and the 1940s. Shown here with an extra fine gold nib.

 

This version is a push-button fountain pen in which the rear cap is not unscrewed to access the metal push-button, but the cap itself is the push-button to move the push-button clip inside and thus fill the ink into the ink sac.

 

A beautiful piece of Montblanc history.