4GB STICK For HP-Compaq Pavilion Series g6-1c53nr g6-1c54wm g6-1c55ca g6-1c55nr g6-1c56nr g6-1c57dx g6-1c58ca g6-1c59nr g6-1c60ca g6-1c61ca g6-1c62us g6-1c64ca g6-1c70ca g6-1c71ca g6-1c74ca g6-1c75ca g6-1c77nr g6-1c79nr g6-1c81nr g6-1c87nr g6-1d20ca g6-1d40ca g6-1d50ca g6-1d53ca g6-1d60ca g6-1d60us g6-1d62nr g6-1d63nr g6-1d70ca g6-1d70us g6-1d71nr g6-1d72nr g6-1d73ca g6-1d73us. SO-DIMM DDR3 NON-ECC PC3-8500 1066MHz RAM Memory. Genuine A-Tech Brand. 4GB STICK 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 Pavilion Series. (See Compatibility List Below)