8GB DDR3 Memory RAM kit (2 x 4GB) for Lenovo ThinkPad X220 X220i Memory Size: 8GB Kit (2 x 4GB) *There are two (2) 4GB DDR3 memory modules in this kit Memory Type: DDR3 SDRAM Number of Pins: 204 Memory Speed: PC3-10600 DDR3-1333 (1333MHz) LIFETIME WARRANTY and free Tech Support