CMS 16GB (2X8GB) DDR3 10600 1333MHZ Non ECC SODIMM Memory Ram Upgrade Compatible with Lenovo® Thinkpad T420 4177, 4178, 4180, 4236 Series - A13 at Amazon.com
OFFTEK 4GB Replacement Memory RAM Upgrade for IBM-Lenovo ThinkPad T420 (DDR3-12800) Laptop Memory at Amazon.com
CMS 16GB (2X8GB) DDR3 10600 1333MHZ Non ECC SODIMM Memory Ram Upgrade Compatible with Lenovo® Thinkpad T420 4177, 4178, 4180, 4236 Series - A13 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
Let's get that bad boy some 16GB RAM and new SSD in addition to the i7 quad core installed lately 😁 : r/thinkpad
Rent a Lenovo ThinkPad T420 with WiMax Verizon, 500gb HD, 16gb RAM, i5 Intel 2.5ghz
How to Replace or Upgrade RAM Lenovo T420 - YouTube
A-Tech 16GB Kit (2x8GB) Memory RAM for Lenovo Thinkpad X250 - DDR3 1333MHz PC3-10600 Non ECC SO-DIMM 2Rx8 1.5V - Laptop & Notebook at Amazon.com