- Whelen 2900 series
The Whelen 2900 Series is a group of
Omnidirectional Civil defense sirens similar to theFederal signal modulator . Each model begins with 2900 and the model numbers change due to the different amounts of disks on the siren. These sirens are used (along with the Federal Signal 2001 series) in replacement of theThunderbolt siren .
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