The present invention relates to a device for delivery of predetermined doses of liquid medicament. According to the present invention, the device is adapted to be in a medicament delivery state and in a medicament non-delivery state. Further, the device is adapted to comprise: a cartridge housing comprising a cartridge adapted to contain the liquid medicament and a piston sealingly and slidably arranged in said cartridge a proximal part provided with a thread in its exterior surface and a distal part comprising a dose setting member with a thread in its interior surface and adapted to be screw threaded on the proximal part of the device to set a volume dose and an elongated threaded plunger rod adapted to be screwed into the cartridge housing, wherein the proximal end of the plunger rod is adapted to be in contact with the piston. The device becomes shorter every time a dose has been set and delivered.
