A medicament delivery device comprising a housing (10 110) a medicament container holder (12 120) rotatably locked but slidable connected to said housing, the medicament holder comprising first mix engagement means (28 126) on its outer surface, and second linear guide means a multi-chamber medicament container (14 130) arranged within the container holder, a plunger rod (60 140) comprising first holding means (58 146) on its outer circumferential surface drive force means (64 142) capable of pushing said plunger rod characterised in that said device further comprises manual mixing means (44, 148) comprising a rotatable manual knob (62,186) protruding from the distal end of the housing and a mix member (48, 149) comprising flexible holding means (52 160) releasibly engaged to the first holding means (58 146) for holding the plunger rod and thereby the drive force means in a pre-tensioned state and second mix engagement means (46 150) arranged to cooperate with the first mix engagement means (28 126) for linearly and distally displacing said container holder into the housing when said manual knob is rotated, such that the distal displacement of the container holder causes a distal displacement of the container in relation to the plunger rod, whereby the plunger rod forces the distal stopper to be proximally displaced and thereby a mixing of the components is performed.
