Needle cover assembly to be used with a medicament delivery device, wherein said needle cover assembly is disposable and comprises: - a retainer element connectable to a medicament container holder, - a hub having a longitudinal axis and comprising a double pointed injection needle with a proximal needle end and a distal needle end, wherein the proximal needle end projects a distance from the hub along the longitudinal axis, and - a shield covering at least the proximal needle end and a portion of the hub, - said shield comprises a detachable element, - the shield is attached to the hub when said detachable element is attached to the shield, corresponding to an untampered state, and - that the shield is released and is telescopically movable in relation to the hub along the longitudinal axis when said detachable element is detached from the shield corresponding to an activated state, - the shield is arranged with a proximal central opening for permitting extension of the needle there through, - a resilient element positioned between the hub and the shield, said resilient element being arranged to urge the hub and the shield apart such that the shield when in activated state is urged to automatically move into a position where it covers the proximal end of the injection needle, - a guiding system wherein the shield is guided along the outside surface of the hub and is telescopically movable in a longitudinal direction in relation to said hub, the guiding system comprising at least one, preferably at least two inwardly directed projections provided on said shield, at least one, preferably at least two guiding slots on said hub, wherein the projections on the shield are arranged to be guided in the guiding slots on the hub by means of sliding and locking elements for engaging the projections on said shield and irreversibly locking the shield in relation to the hub; characterised in that the shield is arranged with a detachable needle seal covering the central opening in an untampered state, - a protective removable impermeable seal arranged to cooperate with the shield in an untampered state to seal off a distal end of the needle cover assembly, wherein the seal and the shield completely covers the hub and the injection needle and provides a sterile confinement for the hub and the injection needle and provides a container. - a retainer element connectable to a medicament container holder, - a hub having a longitudinal axis and comprising a double pointed injection needle with a proximal needle end and a distal needle end, wherein the proximal needle end projects a distance from the hub along the longitudinal axis, and - a shield covering at least the proximal needle end and a portion of the hub, - said shield comprises a detachable element, - the shield is attached to the hub when said detachable element is attached to the shield, corresponding to an untampered state, and - that the shield is released and is telescopically movable in relation to the hub along the longitudinal axis when said detachable element is detached from the shield corresponding to an activated state, - the shield is arranged with a proximal central opening for permitting extension of the needle there through, - a resilient element positioned between the hub and the shield, said resilient element being arranged to urge the hub and the shield apart such that the shield when in activated state is urged to automatically move into a position where it covers the proximal end of the injection needle, - a guiding system wherein the shield is guided along the outside surface of the hub and is telescopically movable in a longitudinal direction in relation to said hub, the guiding system comprising at least one, preferably at least two inwardly directed projections provided on said shield, at least one, preferably at least two guiding slots on said hub, wherein the projections on the shield are arranged to be guided in the guiding slots on the hub by means of sliding and locking elements for engaging the projections on said shield and irreversibly locking the shield in relation to the hub; characterised in that the shield is arranged with a detachable needle seal covering the central opening in an untampered state, - a protective removable impermeable seal arranged to cooperate with the shield in an untampered state to seal off a distal end of the needle cover assembly, wherein the seal and the shield completely covers the hub and the injection needle and provides a sterile confinement for the hub and the injection needle and provides a container.