Years ago a friend of mine had bought an ambulance with a Unity pushbutton SiTron siren. I really liked it. Turns out that Summers Coach in Duncanville,TX who did his ambulance conversion exclusively used Unity lights and sirens on their ambulance builds unless the customer specified otherwise. So after seeing how well my friend's SiTron worked, I decided to find one to use on one of our ambulances. Back then you could deal with Unity directly, which I had done numerous times on lighting products; so I called them about getting a SiTron. Turns out that they had a few refurbished units in stock, so I got one for $50. That siren went on our '72 high top Cadillac ambulance along with a roof-mounted Q. Quite a combination, and both did an excellent job of clearing traffic. Nice thing was that Caddie had twin batteries and a 150-amp. L-N alternator. I could run both of those sirens plus all the lights w/o having anything dim down!