A device (1) for automatic injection of a product into an injection site, the injection device (1) comprising: a housing (9, 11, 68, 72, 93), a container (5) with an injection needle (6) having a tip, the container (5) being movable relative to the housing (9, 11, 68, 72, 93) between at least an initial position, in which the tip of the injection needle (6) is contained within the housing (9, 11, 68, 72, 93), and an insertion position, in which the tip of the injection needle (6) is not contained within the housing (9, 11, 68, 72, 93), a needle shield (2) covering the tip of the injection needle (6), a deshielder (2a) coupled with the housing (9, 11, 68, 72, 93) including: a cap (90) engaged with the needle shield (2), a ring (91) engaged with the housing (9, 11, 68, 72, 93)； and, breakable bridges (92) connecting the cap (90) and the ring (91), wherein, in an initial pre-use state, the cap (90) being connected with the ring (91) by the bridges (92), with the needle shield (2) covering the needle (6), wherein, the cap (90) being removable from the ring (91) without rotation and with sufficient distal pulling force being applied to the cap (90) away from the ring (91) so as to cause breaking of the bridges (92), and wherein, the cap (90) being removed from the ring (91) with the ring (91) remaining fixed to the housing (9, 11, 68, 72, 93), removal of the cap (90) from the ring (91) causing removal of the needle shield (2) from the needle (6).
