ACA went bankrupt in 1992 and was bought by Hormann and was re-branded as ASC in 1994. They re-branded ACA's existing sirens per the buyout and slowly discontinued them over the years.
I really like the idea and philosophy of Sentry Siren. Electro-mechanical, omni-directional sirens with ominous tones. Rotating sirens are cool, but you have another maintenance item with the rotator assembly.
Wow that was amazing. You would think people living near a nuclear power plant would know what to do in an emergency, especially after the 3 mile island incident...