A device (1) for the injection of a product (7) into an injection zone (10), said device comprising: a cover (10) having a longitudinal axis A and sized and having a shape to be able to receive a container (2) for the product to be injected, said container being aligned on said longitudinal axis A, said container being substantially closed at a proximal end by a stopping element (6), said stopping element being able to move distally within said container to expel the product to be injected, and at a distal end by a needle (3) for the exit of the product to be injected, said container being movable with respect to said cover between a first position, in the that the needle does not extend beyond a distal end of the cover, and a second position, spaced distally with respect to said first position, in which the needle extends beyond the e xtreme end of the cover, a pushing means (8), coupled to said cover and designed to produce a distal force along a longitudinal axis B when it goes from a first state to a second state, said second state being less tensed said first state, said longitudinal axis B being spaced laterally with respect to said longitudinal axis A along a transverse direction R, a link means (60) for coupling said thrust means to said container at least from said first position up to said second position of the container, said link means having a shape and being sized to transmit said distal force to said container when said pushing means goes from its first state to its second state to move said container from its first position to its second position, a retaining means (70) coupled to said container and to said cover in the first position of the container, to maintain removably d said pushing means in its first state, said retention means being able to move from a passive condition, in which it maintains said pushing means in its first state, to an active condition, in which said pushing means is free of expanding to its second state, wherein the device
