[Wolf]

It looks like a fancier version of the intake air temp mod that people sell on ebay all the time.

All it's doing is telling your car's ECU that the temperature of the air coming into the engine is colder than it actually is (IAT sensor mentioned on the auction is the Idle Air Temperature). Colder air is denser, so the computer advances the ignition and adds more fuel, giving you an increase in power.

It's a pretty ghetto mod, and it's a total ripoff at $50.
There are also eBay auctions that tell you how to relocate the IAT sensor to the front of the engine compartment, so it also gets colder air, having the same effect.

Remember: Speed costs money, how fast do you want to go?