I have a 71 SS clone and I am adding the dual horns. I am checking that all SS came with dual horns? I also want to know if anyone knows the correct letter sounds for the SS? Example there is a letter code H on one of my horns. I was told that they have different Hi and Low sounds is this correct? Thanks John

The two horns are high and Low. you need 1 high and 1 low

I believe dual horns were an option on all cars.