The Thunderbolt is the most influential siren in the world. Starting production in the 50's, this siren has come in a variety of different models:
Federal Signal Thunderbolt 1000
Federal Signal Thunderbolt 1000T
Federal Signal Thunderbolt 1003
Roundhorn Federal Signal Thunderbolt 1000
The 1000 was the first model. The only difference between it and the 1000T was the 1000T was dual-toned and a lower pitch. The 1003 could switch tones and could THEORETICALLY be programmed to play simple songs, but the only official tones for it that are near musical are Alternate Wail and the Hi-Lo.
Original Thunderbolt from 1953. Known as a "Bumblebolt" for the paint job. Also known as a Jailbar thunderbolt, which only around 50 remain (as of April 2024) due to the bars in the horn. This siren was refurbished and is in Park City, Kansas. This was the 75th ever Thunderbolt. "