Hi yes, that is the siren box outside the house, which is wireless. I haven't replaced the battery yet, but the siren is now not working (perhaps due to weak battery).
I have a Pyronix Enforcer (Wireless) installed in 2012 which has been working well so far. The original installer replaced the external batteries once in between. For over two weeks, I have see the an alert in the control panel which says: Siren 1 Low Battery. I have opened the external siren...