The present invention relates to a medicament delivery device comprising an elongated housing (10, 10) having opposite distal and proximal ends, a medicament container (18 18) arranged inside said housing, a medicament delivery member (16 16) attachable to said medicament container a plunger rod (22 22) arranged to act on a stopper (20 20) inside said medicament container driving means arranged to interact with said plunger rod wherein said device further comprises an operation member (38 38) transversally protruding through an elongated opening (39 39) on the longitudinal surface of the elongated housing and interactively connected to the driving means for both setting and actuating the delivery of a dose of medicament.
