The device (1) for the sealed connection to a receptacle (2) of an accessory (3), the active proximal part (9) of which is intended to be connected to the inside (4) of the receptacle (2) by an opening (7) in the receptacle (2), includes a first element (15), a second element (16) and a chamber (18), the first element (15) including a proximal end part (32) which is secured by sliding in the proximal direction, with insertion of a lateral sealing component (22), onto a matching part (19) of the receptacle (2), in the proximal direction, the transverse head (14) corresponding to the lower surface of the first element (15) and being provided with a lateral head sealing component (28) and the second element (16) being capable of being pre-assembled with the first element (15) by axial sliding in the proximal direction.
