This part is the Keyboard and Palmrest Assembly (C-Cover) for the Lenovo ThinkPad X1 Carbon Gen 12. Part Identification: Parts No: SN20Z77278 Model Number (M/N): CS21X1BL-84US ODM P/N: PK131U91B00 LCID: ENG, 409 (US English Layout) Compatibility: This assembly is unique to the ThinkPad X1 Carbon Gen 12. Because the X1 Carbon uses a "top-load" keyboard design that is integrated into the palmrest structure, this is the complete top deck of the laptop.
eBay