CT2CP25664BF1339 is a 4GB kit consisting of (2) 2GB DDR3 Notebook modules that operates at speeds up to 1333 MT/s and has a CL9 latency. It is dual voltage and can operate at 1.35V or 1.5V. It is Unbuffered and is non-ECC. It conforms to the industry standard SODIMM layout of 204 pins and is compatible with computers that take DDR3 SODIMM memory.