Abstract: The invention relates to a theft-deterrent device which is intended to be attached to and locked on theft-attractive goods (10) and which is constructed to coact with a device release means (8) for release of the device from said goods. The theft-deterrent device includes a first unit (2) which comprises a base element (3) and a connecting element (4) which projects out from the base element and which is intended for insertion through the goods (10), and a second unit in the form of a locking element (6) which is intended to be placed on the connecting element (4) and locked to said element against movement in a direction away from the base element (3) so as to secure the device firmly to said goods (10). The locking element (6) is constructed for release from the connecting element (5) by the action of a gasflow delivered to the locking element (6). The invention also relates to a locking element (6) for a theft-deterrent device, and to a theft-deterrent device release means (8).