An injection device having a first sub-assembly (110) comprises a housing(111) and a chamber (112). Thecham-ber is disposed within the housing and has proximal and distal ends, aninner surface and an exit aperture (114). The sub-assemblycomprises a stopper (113) movably disposed within the chamber. The stopper hasan outer surface substantially in contact with theinner surface about its perimeter. The sub-assembly comprises a port (118)adapted to receive a container (1199) containing aflu-id. The stopper is fixed with respect to the housing and movement of theport causes movement of the exit aperture in relation tothe stopper.
