A medicament delivery device comprising: - a tubular housing having a proximal end and an opposite distal end; - drive means configured to act on a medicament container for expelling a medicament; - holding means configured to hold said drive means in a pre-tensioned state; - activation means configured to interact with said holding means for releasing said drive means from the pre-tensioned state, wherein the activation means is a tubular activation member slidably and coaxially arranged in relation to the tubular housing; and a container holder coaxially arranged within the tubular activation member and fixedly attached to the tubular housing, wherein the medicament container is arranged within said container holder and wherein said medicament container comprises a pre-determined volume of medicament, a slidable stopper and a delivery member, wherein the drive means comprises a plunger rod and a first resilient member which is pre-tensioned arranged within the plunger rod and wherein said plunger rod is arranged to be in contact with the slidable stopper within the medicament container, wherein the holding means are a tubular extension part fixedly connected to the distal end of the tubular housing and a tubular operation member which is rotatably and coaxially arranged on a proximal part of the tubular extension part, being interactively connected both to the tubular extension part and to the tubular activation member, such that when said tubular activation member is pressed against a delivery site said tubular operation member is rotated in relation to said tubular extension part whereby said drive means are released from the pre-tensioned state for exerting a pressure on the slidable stopper and thereby expelling the medicament, wherein the device further comprises feedback means configured to interact both with said holding means and with said drive means for generating an audible and/or tactile and/or visual signal indicating that the medicament has been completely expelled, characterized in that said feedback means is a longitudinally extending signal generating member interactively connected to said tubular extension part and to said drive means, such that when the plunger rod is completely released from the tubular extension part and the longitudinally extending signal generating member, the longitudinally extending signal generating member is released from said tubular extension part and displaced distally by a remaining force of the first resilient member for generating an audible and/or tactile and/or visual signal indicating that the medicament has been completely expelled, wherein the longitudinally extending signal generating member is releasable arranged on an inner surface of the tubular extension part, wherein said signal generating member is an elongated u-shaped bracket comprising a transversal wall and two longitudinally extending flexible arms provided with angled support members extending radially outward, and wherein said support members are adapted to rest on an annular proximal end of the tubular extension part when the drive means are in the pre-tensioned state, wherein the transversal wall of the U-bracket is arranged at a predetermined distance D from an inner distal surface of said tubular extension part when the drive means are in the pre-tensioned state, wherein the first resilient member has a first end abutting the proximal end wall of the plunger rod and a second end abutting a transversal wall of the signal generating member, wherein an audible signal is generated for confirming that a medicament delivery has been performed when the distal end of the plunger rod has passed the supporting members, such that the longitudinally extending flexible arms, with the support members, are released and allowed to move in a radial inward direction, enabling the U-bracket to move the predetermined distance D in the distal direction by a remaining force exerted by said first resilient member, whereby the transversal wall of the bracket hits the inner distal surface of said tubular extension part. - a tubular housing having a proximal end and an opposite distal end; - drive means configured to act on a medicament container for expelling a medicament; - holding means configured to hold said drive means in a pre-tensioned state; - activation means configured to interact with said holding means for releasing said drive means from the pre-tensioned state, wherein the activation means is a tubular activation member slidably and coaxially arranged in relation to the tubular housing; and