The radio-external siren hits with an enormous sound pressure of 105 d B & the intense flashlight of every offender in the flight. Moreover, it has a visible external mark for professional safety & deters thereby potential offenders. The wireless siren possesses an inside lying antenna & communicates bi-directional with the alarm centre. Each manipulation attempt releases thus an alarm at the plant. By Visual signals, the siren acknowledges the enable/disable of the attachment. The flash rate of the xenon lamp can be adjusted individually.