Will this carbon fiber pattern fade or yellow over time?

Carbon fiber weave patterns are resistant to UV degradation, but sealing the edges after installation helps prevent moisture from getting underneath and causing discoloration. A clear coat trim protectant applied to the edges extends life significantly.

What's the best way to seal the edges once these are mounted?

After mounting at the factory points, apply a flexible silicone sealant or trim-specific edge sealer around the perimeter where the visor meets the window frame. This blocks water and air infiltration without interfering with the carbon weave appearance.

Do these need primer or paint before installation?

These arrive with a finished carbon fiber pattern ready to install as-is. No paint or primer required. If you want to color-match them or apply additional protective coating, that's a personal choice—but it's not necessary for function or durability out of the box.