Lenovo ThinkPad x301 Mods: BIOS, Bluetooth and microSD Drive - YouTube
X301, The Ultimate Rebuild
128gb Micro SATA SSD Flash for IBM ThinkPad X301 Laptop Notebook Hard Disk Drive for sale online | eBay
Lenovo Thinkpad X301 SSD upgrade using 1.8" mSATA adapter
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