Simplex 4904-9139 Category : Simplex I believe that this strobe plate was designed to be used with bells, such as the Simplex 2901-9333. Brand SimplexModel 4904-9139Manufacturer SimplexType Alarm (Strobe Plate)
Simplex 2901-9833 Category : SimplexI have several of these horns because I’ve had several of them unexpectedly break on me.
