Abstract: A security device for tagging a bottle has a body defining a sleeve into which part of the bottle neck and its closure are received. A housing is defined to one side of the sleeve and first and second catch members are pivoted within the housing for movement between free and locking positions. When in their locking positions, the catch members project into the sleeve to engage behind a shoulder on the bottle neck or the closure, to resist removal of the device. An operating member is also pivoted to the housing for movement between open and closed positions, springs being arranged between the operating member and the first and second catch members to urge the catch members to their respective locking positions. A magnetically-releasable latch is arranged to hold the operating member in its closed position unless the latch member is acted upon by an external magnetic field.