Refurbished: Lenovo ThinkPad T420 14.1" Windows 7 Professional 64-Bit Notebook - Newegg.com
A-Tech 8GB RAM for Lenovo THINKPAD T420 4177 | DDR3 1333MHz SODIMM PC3-10600 204-Pin Non-ECC Memory Upgrade Module at Amazon.com
16GB KIT (2 x 8GB) for IBM Lenovo ThinkPad T Series T420 T420i T420s T520 T520i. SO-DIMM DDR3 Non-ECC PC3-10600 1333MHz RAM Memory. Genuine A-Tech Brand. at Amazon.com