As Hookie says it is a variable resistor in a fancy box. All it does is alter the signal from the air temp sensor to the ecu, the ecu sees a low temp and dumps more fuel, the O2 sensor then corrects any over fueling.
Save your Brass and lookout for a Power Commander 3. Install a choice of maps.
Warning this becomes addictive, very soon the choice of maps will not be enough, you will think there is more to be had. At this point you will start changing end cans and this opens up more maps. Then the induction system, more maps to try. Then the entire exhaust system will be changed with more maps to choose.
The next stage will be a custom map on a dyno. At this stage your hunger should be sated and it will for a while... Until you read more stuff and make another exhaust system and fit an ECU from a 130bhp TL 1000. This makes the 'bike unrideable and uses fuel at an astonishing rate. 18 mpg, black smoke and flames, but it has a mad powerband similar to a 2 stroke of 800 rpm that starts at 7200 rpm and finishers at 8k.
You take it for another dyno session, the same man who by now are on 1st name terms with shakes his head and says " It was spot on, what did you do"?
He sets it up again after removing the TL1000 ecu and you tell yourself it's great, you ride home telling yourself it's the best it's ever been. You smile inside your lid.
12 months later you read stuff about the benefits of a 2 into 1 system on a V twin. You remove the twin cans and fabricate a 2 into 1. It does "feel better". You are should be content. You know the next dyno session is immanent, but you put off the inevitable.
For Now.