A-Tech 4GB KIT 2 x 2GB HP-Compaq Presario Notebook CQ57-252SA CQ57-253SA CQ57-256SA CQ57-301SA CQ57-302SA CQ57-303SA CQ57-310US CQ57-314NR CQ57-315NR SO-DIMM DDR3 NON-ECC PC3-8500 1066MHz RAM Memory 4GB KIT (2 x 2GB) SO-DIMM DDR3 NON-ECC PC3-8500 1066MHz RAM Memory Genuine A-Tech Memory Lifetime Warranty Toll Free Technical Support 1-866-557-4527 Designed For HP-Compaq Presario Notebook Series. (See Compatibility List Below)