The invention provides a jacket assembly (2) for a cartridge (40). The jacket assembly (2) is adapted to be received by a dispensing device (38). The jacket assembly (2.) comprises a body (4) having a first end (8), a second end (10), and a wall (12) extending therebetween. An alignment member (14) is located on the wall (12), the alignment member (14) being substantially rectilinear in shape. Particularly, but not exclusively, the invention relates to a jacket assembly for an aerosol cartridge, for use in a device for dispensing a fluid for fragrancing, deodorising or sanitising air. According to a further aspect of the present invention there is provided a jacket and refill cartridge assembly； a dispensing device adapted to receive a jacket assembly； a dispensing device assembly comprising a dispensing device, a jacket assembly and a refill cartridge； a dispensing device adapted to receive a jacket assembly and refill cartridge.
