Do these diffusers come with mounting hardware?

The set includes the diffuser pieces only. You'll need to source fasteners or adhesive appropriate for your bumper mounting points — check your OEM bumper design to confirm hole location and spacing before installation.

What prep work do these need before I paint them?

Sand the surface and clean thoroughly before applying your chosen primer and paint. Polyurethane absorbs finish well when prepped properly — a smooth, clean surface ensures even color and adhesion.

My diffusers arrived with slight warping from shipping — what do I do?

Polyurethane can deform during transit. Place the diffusers in direct sunlight for a few hours to let them return to their original shape naturally — no heat gun or oven needed. They'll settle back into form once installed and exposed to normal outdoor temperatures.