was an option on Aero K's s14s, Ive never actually wired it up, its been just sitting in my car for like 4 years. I wired up the lights for that ricer look and all, but never actually hooked it up. It has red LED's in it I think.
I had the pigtail but lost it, however here is a wiring guide:
http://zilvia.net/f/showthread.php?t=155167
here are the pics, notice a scratch in the plastic of the middle gauge.
175 shipped.