The invention relates to a disposable drug delivery device (1) for selecting and dispensing a number of user variable doses of a medicament. The device (1) comprises a housing (10, 20), a cartridge holder (11) for retaining a cartridge (80) containing the medicament, a piston rod (30) displaceable relative to the cartridge holder (11), a driver (40) coupled to the piston rod (30), a display member (60) for indicating a set dose and being coupled to the housing (10, 20) and to the driver (40), and a button (70) coupled to the display member (60) and to the driver (40).
