4GB KIT (2 x 2GB) For HP-Compaq HP Pavilion Desktop A6552.sc A6552f A6553.fr A6553.is A6553.sc A6554.be A6554.ch A6554.de A6554f A6555.fr A6555.it A6557.uk A6558.fr A6558f A6560a A6560d A6560t A6560z A6561.af A6561.at A6561.es A6561.it A6561.ru A6561.uk A6563.cs A6564.de A6565.gr A6565.it A6565tw A6567c A6568hk A6569.de A6570.at A6570.es A6570a A6572l A6573.fr A6573l A6575.at A6575.es. DIMM DDR2 NON-ECC PC2-6400 800MHz RAM Memory. Genuine A-Tech Brand. 4GB KIT (2 x 2GB) 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 HP Pavilion Desktop. (See Compatibility List Below)