A security system includes a security tag (20) and a releaser which allows tags to be connected to an article. The system uses two arms on a releasing device which fit into respective channels on the security tags. The arms are used to activate a releasing mechanism which releases an attaching member which allows the security tag to be coupled to an article. By using arms which fit into respective channels in the release, this makes it very difficult for a thief to overcome the releasing mechanism without the pre-designed releaser, which will not generally be made available to the public.
