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A blue F2
The F-2 Is a Small Industrial Siren by Sentry Siren..
On the Sentry Siren Website it Says:
The F-2 employs a carefully machined and balanced aluminum fan and housing, and aluminum, powder coated projectors. The air intake is screened to protect against foreign matter. Corrosion protected, it is suitable for indoor or outdoor installation. Each F-2 is hand assembled by our highly trained staff to exacting specifications. Additionally, we test each individual siren at the factory before delivery, ensuring that you receive only the highest quality utility siren every time.