You can also supplement the SECVEST® 868 with a wireless outdoor siren which is equipped with a 105 d B alarm. This wireless outdoor siren has bidirectional duplex antenna technology. Thus the siren messages are forwarded to the Secvest® 2WAY-centre. Any attempt at manipulation will trigger an alarm. The sabotage-protected, weather-resistant metal case is attached on the outside wall where it can easily be seen. Often, the presence of an outside siren is enough to deter potential thieves.