Siemens U-MHST-MCS I believe that this alarm has the ability to produce multiple tones. Brand SiemensModel U-MHST-MCSManufacturer SiemensType Alarm (Horn/Strobe)
Simplex 4903-9417 Category : SimplexThis is a SmartSync TrueAlert which I am able to use with my Simplex 4010.
GE 278B-1110 Category : GEThis is the non-addressable version of the EST SIGA-278. This particular unit is branded by GE.