An assembly (100) for a drug delivery device is presented. The assembly comprises a housing (10) with a main axis (X), a dose setting member (2) being rotatable with respect to the housing (10) for setting a dose of a drug, an activation member (1) being axially movable with respect to the housing (10) for dispensing the dose from the drug delivery device, and a rotation member (5) being arranged between the activation member (1) and the dose setting member (2). The assembly (100) is configured such that the rotation member (5) is rotatable with respect to the dose setting member (2) and the activation member (1), wherein the outer surface (21) of the assembly (100) comprises the outer surface (22) of the rotation member (5).Linvention concerne un ensemble (100) pour un dispositif dadministration de médicament. Lensemble comprend un boîtier (10) ayant un axe principal (X), un élément de réglage de dose (2) pouvant tourner par rapport au boîtier (10) pour régler une dose dun médicament, un élément dactivation (1) mobile axialement par rapport au boîtier (10) pour distribuer la dose du dispositif dadministration de médicament, et un élément de rotation (5) placé entre lélément dactivation (1) et lélément de réglage de dose (2). Lensemble (100) est configuré de telle sorte que lélément de rotation (5) peut tourner par rapport à lélément de réglage de dose (2) et lélément dactivation (1), la surface extérieure (21) de lensemble (100) comprenant la surface extérieure (22) de lélément de rotation (5).
