1GB STICK For HP-Compaq Presario CQ Series CQ5116ES CQ5116FR CQ5118LA CQ5120IT CQ5121AF CQ5121IT CQ5121PT CQ5121SC CQ5122NL CQ5122PT CQ5123F CQ5123IT CQ5125IT CQ5135ES CQ5140SC CQ5143SC CQ5145SC CQ5205Y CQ5210F CQ5210LA CQ5210Y CQ5215LA CQ5216LA CQ5217LA CQ5218F CQ5218LA CQ5221F CQ5300F CQ5300Y CQ5328F CQ5500F CQ5500Y CQ5519F CQ5521F CQ5600 CQ5600F CQ5600Y CQ5602F CQ5603F CQ5604F CQ5619F. DIMM DDR2 NON-ECC PC2-6400 800MHz RAM Memory. Genuine A-Tech Brand. 1GB STICK DIMM DDR2 NON-ECC PC2-6400 800MHz RAM Memory Genuine A-Tech Memory Lifetime Warranty Toll Free Technical Support 1-866-557-4527 Designed For HP-Compaq Presario CQ Series. (See Compatibility List Below)