A drug delivery device for delivering a dose of a medicament, wherein the drug delivery device comprises: - a housing assembly comprising an elongate housing structure (140, 240); - a drive mechanism for delivering the dose, the drive mechanism being arranged within the elongate housing structure (140, 210), wherein the drive mechanism is adapted to expel the dose of the medicament, in response to activation; - an activation mechanism comprising a rotatable tubular activation member adapted to activate the drive mechanism, in response to an axial movement of the activation member, wherein the activation member is adapted to be arranged in: (i) a first angular position, wherein the activation of the drive mechanism is disabled, (ii) a second angular position, wherein the activation member is arranged to be movable in the axial direction, and thereby allows an axial movement enabling activation of the drive mechanism; characterized in that the drug delivery device further comprises a ring member surrounding the activation member; wherein the ring member is connected to the housing assembly, wherein the ring member is arranged to be axially fixed and movable in the rotational direction relative to the housing assembly, wherein the ring member is axially splined to the activation member, whereby the ring member is rotationally locked and movable in the axial direction relative to the activation member; whereby the ring member is adapted to transfer a rotation to the activation member from the first position to the second position, in response to a rotation of the ring member, whereby a user can rotate the activation member without unintentionally activating the drive mechanism. - a housing assembly comprising an elongate housing structure (140, 240); - a drive mechanism for delivering the dose, the drive mechanism being arranged within the elongate housing structure (140, 210), wherein the drive mechanism is adapted to expel the dose of the medicament, in response to activation; - an activation mechanism comprising a rotatable tubular activation member adapted to activate the drive mechanism, in response to an axial movement of the activation member, wherein the activation member is adapted to be arranged in: (i) a first angular position, wherein the activation of the drive mechanism is disabled, (ii) a second angular position, wherein the activation member is arranged to be movable in the axial direction, and thereby allows an axial movement enabling activation of the drive mechanism; characterized in that the drug delivery device further comprises a ring member surrounding the activation member; wherein the ring member is connected to the housing assembly, wherein the ring member is arranged to be axially fixed and movable in the rotational direction relative to the housing assembly, wherein the ring member is axially splined to the activation member, whereby the ring member is rotationally locked and movable in the axial direction relative to the activation member; whereby the ring member is adapted to transfer a rotation to the activation member from the first position to the second position, in response to a rotation of the ring member, whereby a user can rotate the activation member without unintentionally activating the drive mechanism.