Abstract: Disclosed is a packaging for a number of pre-filled drug cartridges comprising a body to which an infusion set with tubing and needle can be fitted, the body having an open rear end, wherein a stopper is slidably disposed within the body, wherein a peg is arranged on the packaging, the peg having a height which is such that when a cartridge is being put on the peg with the rear end and pushed against it until the rear end abuts a surface of the packaging, the stopper is moved within the body by such a distance that a predetermined volume of a medicament is displaced from the cartridge for priming the cartridge and infusion set.