Will this diffuser clear the bumper on inclines or steep driveways?

Hunter-style diffusers sit close to the factory bumper profile. Verify ground clearance on your vehicle's specific setup, especially if you've lowered it or plan to use aggressive approach angles. Measure from your lowest rear point to the driveway edge before installation.

Does this come with mounting hardware and fasteners?

The assembly includes the five diffuser pieces. Confirm mounting locations against your OEM bumper and gather fasteners appropriate for your installation method before beginning work.

Is the Hunter style purely cosmetic or does it provide functional downforce?

Hunter-style diffusers are designed for visual enhancement. While the geometry complements aerodynamic lines, functional downforce depends on vehicle speed and overall aero package. This piece integrates the look; validate performance claims against your specific use case and speed range.