How does a penis pump work?!
Question: How does a penis pump work?
Your friend is probably lying. Make him prove it!
Penis Pumps are simple vacuum suction devices. They create an erection by sucking blood into the penis, and keeps it there as long as the vacuum is maintained. With consistent steady use over a a great number of months, it might be possible to improve blood volume. I doubt that it adds 3" or any other "back of the Penthouse" boasts.
Used with a cock ring, it can help a person get and keep an erection. Used incorrectly or too aggressively, it can damage the penis, and burst blood vessels causing vascular damage, scarring, and deformity.