Abstract: A cartridge system for use with a drug delivery device (100?), comprising: —a pre-filled cartridge comprising: a) a cartridge body (210) accommodating a drug, b) a piston (250) slidably disposed in the cartridge body (210) and configured for providing a proximal seal, the piston (250) comprising: b1) a piston first member (260) comprising a first material and forming a distal end, a proximal end and a sealing periphery in contact with the cartridge body (210), wherein the distal end is in contact with the drug and wherein the proximal end of the piston first member (260) includes a proximally facing opening, and b2) a piston second member (270) comprising a material of lower compressibility compared to the first material, the piston second member (270) comprising a sleeve-formed portion arranged in the proximally facing opening of the piston first member (260), wherein the piston second member (270) comprises a proximally facing opening forming a socket; and—a plug unit (280) coupleable or coupled into the so

Abstract: A cartridge having a distal end provided with a mechanical coding. The coding has the form of a circular protrusion where the circular outer diameter is dedicated a specific concentration of insulin contained in the cartridge. The distal end of the cartridge is fitted in to a circular contour in the housing. The outer diameter of the protrusion on the distal end of the cartridge is chosen as a larger diameter for a higher concentration of insulin. In this way only a cartridge containing the correct concentration or a lower concentration fits into a delivery system designed for a specific concentration of insulin.

Abstract: A cartridge having a distal end provided with a mechanical coding. The coding has the form of a circular protrusion where the circular outer diameter is dedicated a specific concentration of insulin contained in the cartridge. The distal end of the cartridge is fitted in to a circular contour in the housing. The outer diameter of the protrusion on the distal end of the cartridge is chosen as a larger diameter for a higher concentration of insulin. In this way only a cartridge containing the correct concentration or a lower concentration fits into a delivery system designed for a specific concentration of insulin.

Abstract: A cartridge having a distal end provided with a mechanical coding. The coding has the form of a circular protrusion where the circular outer diameter is dedicated a specific concentration of insulin contained in the cartridge. The distal end of the cartridge is fitted in to a circular contour in the housing. The outer diameter of the protrusion on the distal end of the cartridge is chosen as a larger diameter for a higher concentration of insulin. In this way only a cartridge containing the correct concentration or a lower concentration fits into a delivery system designed for a specific concentration of insulin.

Abstract: A disconnectable connection between a plunger and a plunger rod in a medical delivery system is provided. The plunger comprises a spherical or semi spherical shaped cavity, which is fully encapsulated in the interior of the plunger and connected to the back wall of the plunger through an open orifice. The Plunger rod has a spherical or semispherical portion provided at the distal end, which portion enters into the plunger cavity when the two parts are connected. In order to allow air in the plunger cavity to escape during plunger rod connection, is either the distal portion of the plunger rod or the open orifice in the plunger back wall provided with tracks, slots, apertures or similar geometries.

Abstract: A cartridge having a distal end provided with a mechanical coding. The coding has the form of a circular protrusion where the circular outer diameter is dedicated a specific concentration of insulin contained in the cartridge. The distal end of the cartridge is fitted in to a circular contour in the housing. The outer diameter of the protrusion on the distal end of the cartridge is chosen as a larger diameter for a higher concentration of insulin. In this way only a cartridge containing the correct concentration or a lower concentration fits into a delivery system designed for a specific concentration of insulin.