Vacuum Exhaust Cutout Waterproof and long life. A vacuum exhaust cutout, also known as an electric exhaust cutout or simply an exhaust cutout , is an aftermarket automotive modification designed to alter the exhaust flow of a vehicle's exhaust system. This modification allows the driver to control the sound and performance characteristics of their vehicle's exhaust with the push of a button or the flip of a switch. Vacuum exhaust cutouts are often used to create a more aggressive exhaust note and may provide minor performance benefits.
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