Surprised nobody has posted the web site yet. http://www.lksos.com/ (It kind of looks like a rip-off of ASC)
I actually kind of like these sirens, I can remember they were experimenting around with a Chrysler (it was mounted on a 4 ton truck body) and also had a smaller gas siren. I crack up every time I see the bicycle siren. An effective (but noisy) way to burn down those thighs.