I'd have to take my intake all apart to show it, but Aluminized tubing is standard corrosion resistant exhaust tubing. The guy didn't have any lying around that was the right diameter to fit snugly inside the end of the Z tube and G35 acordian piece to mate them, so he used a machine ("sledge") used to stretch exhuast tubing to a wider diameter (used to make the end of one section of rubing a receptacle for the end of another section to mate them together) so it would fit just right. The piece I have in there is maybe onlt teo inches long; just enough to mate the Z tube and accordian piece, then clamp it together. Works great and the tubing fits very flush inside the tubes and doesn't decrease the inside diameter or hinder airflow at all.