whats with the O2 sensor powerchip?

I have never seen this or heard of it before, an O2 Sensor powerchips. A friend sent me a link and asked if they are any good. Anyone know anything about these. Says it regulates voltage going to the EEC from O2 to manipulate the Air/Fuel for more power. Would that not screw up your air fuel ratio?

Anyways, I always get good answers here, thanks for the help