Do these bolt directly into the factory fog light openings?

Yes, they're designed to use your Sierra's existing mounting points with no drilling or modification needed.

Will these work with my truck's wiring harness?

LED fog lights typically require a plug-and-play connection to factory harnesses. Confirm your truck's electrical setup matches the connector type before installation.

Are the lenses pre-sealed against water and moisture?

The assembly is built as a sealed unit designed for outdoor use, but inspect the seal around the lens during installation—any gaps should be sealed with silicone or weatherproof tape to prevent moisture ingress.