This is a cast aluminum manual air shut off available in

4" opening measures 3.5"

5" opening measures 4.5"

6" opening measures 5.5"

We also offer vinyl coated cable for easier installation.  Cable is sold by the foot, measure length allowing for an additional foot to extend past the turbo.

Air shut offs will mount directly on most turbo housings.  If turbo is a different size, Rubber Intake Elbows are used to connect air shut off to turbo, no air cleaner is used