An administration mechanism (23; 23') for a medicament delivery device comprising a housing, a first resilient member, a plunger rod, a tubular member, a second resilient member, a rod, a feedback member and an end member, the administration mechanism comprising: a movable sleeve (6; 6'), and a delivery member cover (5; 5') having a distal end portion ( 5a; 5a') configured to receive the movable sleeve (6; 6'), and configured to be linearly displaceable between a first position and a second position relative to the movable sleeve (6; 6'), wherein the first position corresponds to an extended position relative to the housing and the second position corresponds to a retracted position relative to the housing, wherein the distal end portion (5a; 5a') has an end face (5c; 5c') defining a guide surface (5d; 5d') and the movable sleeve (6; 6') has a radially outwards extending first follower structure ( 6a; 6a') configured to cooperate with the guide surface (5d; 5d') when the delivery member cover (5; 5') is moved from the first position towards the second position, causing the movable sleeve (6; 6') to move, and wherein the movable sleeve comprises a radially outwards extending second follower structure and the distal end portion of the delivery member cover has a cut-out, characterized in that the cut-out is configured to receive the radially outwards extending second follower structure, wherein the radially outwards extending second follower structure is configured to cooperate with a wall of the cut-out, causing rotation of the movable sleeve when the delivery member cover is moved from the second position towards the first position, wherein the radially outwards extending second follower structure has a triangular shape and the wall of the cut-out is a slanting surface, and wherein the radially outwards extending first follower structure has an oblique surface configured to cooperate with the guide surface, wherein the delivery member cover has a distal end portion and a proximal end portion, wherein the proximal end portion has a generally tubular shape and the distal end portion has two legs (sf), and the delivery member cover is configured to receive the moveable sleeve between the two legs. a movable sleeve (6; 6'), and a delivery member cover (5; 5') having a distal end portion ( 5a; 5a') configured to receive the movable sleeve (6; 6'), and configured to be linearly displaceable between a first position and a second position relative to the movable sleeve (6; 6'), wherein the first position corresponds to an extended position relative to the housing and the second position corresponds to a retracted position relative to the housing, wherein the distal end portion (5a; 5a') has an end face (5c; 5c') defining a guide surface (5d; 5d') and the movable sleeve (6; 6') has a radially outwards extending first follower structure ( 6a; 6a') configured to cooperate with the guide surface (5d; 5d') when the delivery member cover (5; 5') is moved from the first position towards the second position, causing the movable sleeve (6; 6') to move, and wherein the movable sleeve comprises a radially outwards extending second follower structure and the distal end portion of the delivery member cover has a cut-out, characterized in that the cut-out is configured to receive the radially outwards extending second follower structure, wherein the radially outwards extending second follower structure is configured to cooperate with a wall of the cut-out, causing rotation of the movable sleeve when the delivery member cover is moved from the second position towards the first position, wherein the radially outwards extending second follower structure has a triangular shape and the wall of the cut-out is a slanting surface, and wherein the radially outwards extending first follower structure has an oblique surface configured to cooperate with the guide surface, wherein the delivery member cover has a distal end portion and a proximal end portion, wherein the proximal end portion has a generally tubular shape and the distal end portion has two legs (sf), and the delivery member cover is configured to receive the moveable sleeve between the two legs.