Includes NPP valves (NO DFM valves on Z06) System contains SwitchFire™ Technology Valve actuator recalibration REQUIRED after installation. After installation, the exhaust valve actuators should be re-calibrated according to GM Document ID 5406413. BORLA® Performance Industries recommends taking your car to the nearest Chevrolet dealer for exhaust valve recalibration services. Tips NOT included, reuse O.E. tips, or install optional BORLA® tips. See below for additional Product Features & Benefits