One of the schools in my district has a simplex system with simplex 4903’s and Gentex shgs. All on continuous.
My middle school had a notifier system with spscrs. It had the standard notifier message, but the tone was an edwards tone. On their website, I think they call it “3-pulse air horn.”
Do you mean gx90s? The gxs is a remote strobe, and they wouldn’t have a system with just remote strobes