Kingston HyperX Plug n Play 4 GB Kit (2x2GB Modules) 1866MHz DDR3 SODIMM Notebook/Netbook Memory 4 Dual Channel Kit (PC3 15000) 204-Pin KHX1866C11S3P1K2/4G 4GB Kit (2x2GB Modules) of DDR3 Notebook/Netbook Memory Utilizes HyperX module with faster latency timing for higher performance and speed Specifically designed and tested for compatibility in various makes and models of notebook computers From the industry leader in PC memory Non-ECC 1866MHz 204-pin Unbuffered SODIMM type