Kingston HyperX 4GB Kit (2x2GB Modules) 667MHz DDR2 SODIMM Notebook Memory KHX5300S2LLK2/4G 4GB Kit of 667MHz DDR2 Notebook 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 Low-Latency 200-pin unbuffered SODIMM type