*This mod is not scientifically accurate as in real life you cannot hear the sonic boom you produce*
In this mod, it tells you your m/s and whatever you're riding's m/s. If you/what you are riding, go past 343 m/s you hear a sonic boom. The sound for the sonic boom is different depending on if you are riding something or not. Once you reach 343 m/s it will replace your meter to "mach 1" if you go past 686 m/s it will say "mach 2" etc. The max it will say is mach 10+. If you somehow reach 299,792,458 or higher it will change to "Speed of Light" not only that, but your screen should turn black for that moment you reach that absurd speed. This mod is more of a tool for you to test how fast certain transportation methods are.