C8 Corvette Stingray Lower Deflector Panels, GM p/n 84965194.
Intended for non-Z51, but can easily be modified for Z51 version (p/n 84965195) by (on each side) simply removing 3 screws and a sub-panel to unblock airflow to the brake duct.
The panels for sale are item #18 in the GM parts diagram for the front bumper.
Set includes the left and right sides plus screws.
New, never used, nor installed.
Original GM parts.