The pen is a safety of the brand Fabula (maker Aura GmbH, Munich), presumably from the 1920s. With this construction principle the nib is retracted by the twist mechanism so that filling is done via the front opening with a pipette — not via the rear end. Before first ink use it should be checked with water whether the writing instrument is still tight; on leakage the cork seal must be renewed. With nib retracted, the closure mechanism seals the opening, so the ink stays inside.