20 Hp Increase With Chip On E-bay?

I see on E-bay people are selling what looks like a resistor to go on the air temp sensor connection and it will increase your hp by 20 at a cost of only about $3. what is this, a resistor and where does it exactly go?

It's a scam. Have you seen any proof such as independent dyno tests that support their claims? You cannot buy 20 additional horsepower for $3. I don't know how it hooks up.

Clifton