I'm riding behind an '05 STC with the axact same mods as mine, and I noticed other than the red lenses on the rear turn signals, when he brakes, the signals light up. Now on my '05, I have yellow lenses and they only work as turn signals. I am thinking I like his setup better, because the more brake lights on the safer. Can anyone tell me if this is aftermarket, or an option? He was not the original owner.