The present invention relates in one aspect to a housing for an injection device, comprising: - a body (30) to accommodate a drive mechanism (5) to operably engage with a piston (52) of a cartridge (50) filled with a liquid injectable medicament (53), - a cartridge holder (20) having a cartridge receiving space (25) to accommodate the cartridge (50), - wherein the cartridge holder (20) and the body (30) comprise an elongated shape and extend along an axial longitudinal direction (1, 2), - wherein the cartridge holder (20) has an insert section (21) at a proximal end (23), - wherein the body (30) has a receptacle (31) at a distal end (33) to receive the insert section (21) of the cartridge holder (20), - wherein the body (30) comprises a first latch element (34) on an inside (32) of a sidewall (32) of the receptacle (31), - wherein the cartridge holder (20) comprises a first through recess (24) in a sidewall (22) of the insert section (21) which through recess (24) is configured to receive the first latch element (34), wherein the through recess (24) comprises a narrowed neck receiving portion (24a) extending axially into a widened latch receiving portion (24b), wherein a first lateral width (w1) of the neck receiving portion (24a) is smaller than a second lateral width (w2) of the latch receiving portion (24b).La présente invention concerne, dans un aspect, un boîtier pour un dispositif d'injection, comprenant : - un corps (30) pour recevoir un mécanisme d'entraînement (5) pour venir en prise de manière fonctionnelle avec un piston (52) d'une cartouche (50) remplie d'un médicament liquide injectable (53), - un support de cartouche (20) ayant un espace de réception de cartouche (25) pour recevoir la cartouche (50), - le support de cartouche (20) et le corps (30) comprenant une forme allongée et s'étendant le long d'une direction longitudinale axiale (1, 2), - le support de cartouche (20) ayant une section d'insertion (21) à une extrémité proximale (23), - le corps (3
