APR Carbon Fiber Mitsubishi/Evil-R Kit Rear Diffuser With APR Widebody Kit Bumper OnlyDiffusers work in conjunction with other aerodynamic components of a car to help produce downforce. Because your Mitsubishi Evil R Kit displaces air as it moves forward, the air molecules in the rear of the car get disrupted causing a vacuum of low pressure air. Features: To help channel the high speed air flow coming from underneath the car, diffusers redirects the high speed air flow to transition smoothly transition into the low pressure vacuum in