Axiom 4GB DDR3-1333 UDIMM Kit (2 x 2GB) - AX31333N9S/4GK - For Desktop PC - 4 GB (2 x 2GB) - DDR3-1333/PC3-10600 DDR3 SDRAM - 1333 MHz - CL9 - Non-ECC - Unbuffered - 240-pin - UDIMM - Lifetime Warranty

No matter how heavy and numerous the applications that you are using, 1333 MHz memory speed will run them smoothly 4 GB memory allows you to have more programs open at a time DDR3 SDRAM interface synchronizes electrical and clock signals for an efficient data transfer rate