The invention relates to an automatic drug delivery device (10), in particular automatic drug delivery device, for dispensing a fluid product, in particular a fluid medicament, including: • a longitudinal housing (104) • a removable cap (50) • a syringe assembly (200) • a drive mechanism (300) • wherein the loaded drive mechanism is operatively coupled with a safety shield (102) movable within the longitudinal housing (104), • wherein the safety shield (102) is biased into a proximal position in which it protrudes out of the proximal end of the longitudinal housing (104) in order to cover a needle tip (348) of the injection needle (206), and wherein the safety shield (104) is movable into a distal position in which the injection needle (206) is exposed for injection； • wherein the longitudinal housing provides an inner receiving component fixed thereto for receiving a syringe holder and providing a predetermined radial and axial position of the syringe holder within the longitudinal housing； • wherein the syringe assembly is a first syringe assembly and is received within the longitudinal housing by a first syringe holder, wherein the first syringe holder provides an interface between the longitudinal housing and the syringe assembly； and • wherein the longitudinal housing and receiving component is sized and configured to be able to receive a second syringe holder and a second syringe assembly, the second syringe assembly having a different diameter than the first syringe assembly.L'invention concerne un dispositif d'administration de médicament automatique (10), en particulier un dispositif d'administration de médicament automatique, pour distribuer un produit fluide, en particulier un médicament fluide, comprenant : • un boîtier longitudinal (104) • un capuchon amovible (50) • un ensemble seringue (200) • un mécanisme d'entraînement (300) • le mécanisme d'entraînement chargé étant couplé de manière fonctionnelle à une protection de sécurité (102) mobile à l'intér
