BEWARE: Lenovo Thinkpad L15 Gen3 SSD is practically un-upgradeable. Laptop comes with 256GB and bigger SSD is too thick to fit. There also goes a cooling plate on top. : r/thinkpad
1 PC M.2 NGFF SSD to for Lenovo ThinkPad X1 Carbon 20+6pin 26Pin SSD Adapter Board Card for PC Accessories - AliExpress
Lenovo ThinkPad L13 Yoga 13.3" WUXGA (1920 x 1200) Touch 2-in-1 Laptop Core i7-1255U 16GB Memory 512GB SSD Black 21B6A001US - Best Buy
Lenovo Thinkpad E550 SSD and Memory Upgrade - YouTube
Lenovo ThinkPad T460s Long-Term Review: Part 2 - Wireless Docks and Terabyte SSDs - NotebookCheck.net Reviews