Lenovo SYSTEM BOARDS
5B21C21390
is compatible in the following Models:
Lenovo ThinkPad X Series laptops
ThinkPad X1 Carbon - 20QDCTO1WW
X1 Carbon 7th Gen - (Type 20QD, 20QE) Laptop (ThinkPad) - 20QDS5UY0Q
X1 Carbon 7th Gen - (Type 20QD, 20QE) Laptop (ThinkPad) - 20QDSOEL00
ThinkPad X1 Carbon - 20QEW5JU04
ThinkPad X1 Yoga - 20QG52P70F