Okay, I know for a fact that Blanchard has a handful of Sentry's...but what the heck is this?! I hear a Sentry in the background but there's some low sounding siren that sounds dual toned.
https://www.youtube.com/watch?v=CpKHhUJSVo4
(Wasn't sure whether to put this is mystery sirens sticky, but I put it here instead)