8GB 2 x 4GB DDR3 Memory for Lenovo ThinkPad T420 T420i T420s PC3-10600 1333MHz 204 pin SODIMM Laptop Notebook RAM (PARTS-QUICK BRAND) 8GB PC3-10600S DDR3 1333MHz 204 pin SODIMM for Lenovo ThinkPad T420 T420i T420s Capacity: 8GB 2 x 4GB Kit Speed: PC3-10600 DDR3 1333MHz Form Factor: 204 pin SODIMM Halogen Free; ROHS Warranty: Lifetime