The present invention relates to a piston for a cartridge (10) to be filled with a medicament (5), the piston comprising:- a first piston member (16 19 26) comprising a first material providing a distal end face (15), and- a second piston member (18 28) comprising a second material and providing a proximal end face (17 27) facing away from the distal end face (15 25),- wherein the second material comprises a lower compressibility compared to the first material. Moreover, the invention also relates to a cartridge and to a drug delivery device comprising such piston.
