WRITING INSTRUMENT

A writing instrument with an operating side, with a writing side with a nib, with a tank which can be filled with liquid writing medium, with a piston, which is movable within the tank, and with an operating element arranged on the operating side for axial adjustment of the piston within the tank. The writing instrument is characterized in that the operating element can be brought by a user from a first axial position, namely an idle position, in which it is held axially in position in particular with locking, into a second axial position which differs axially from the idle position, namely an operating position, in which the operating element has a larger distance to the nib in comparison with the idle position and in which the operating element can be gripped by the user and moved for the axial adjustment of the piston.