SECURITY DEVICE

摘要

A security device (2) for attachment to a container (7,10) having external walls such that a transponder (20) thereon is located externally of or adjacent to one of said external walls so as to avoid being shielded by a metal layer (21) within the container (7, 10) (e.g. the metal layer within a disk such as a CD or DVD). The security device (2) is arranged to trigger an alarm signal if the container (7, 10) is moved within the range of an alarm unit with the security device (2) attached thereto, and has a releasable locking mechanism (11, 12) to secure it to the container (7,10) such that release of the locking mechanism (11, 12) requires the use of authorised release means. In one embodiment the transponder (20) is located in the vicinity of a window (21A) in a metal layer (21), e.g. at the centre of the disk.