A-Tech 1GB KIT 2 x 512MB HP-Compaq Presario Notebook 2157EA 2158EA 2160EU 2161EA 2161US 2162US 2166 2168AE 2169 2169EA 2170CA 2170US 2171US 2172EA 2172US SO-DIMM DDR NON-ECC PC2100 266MHz RAM Memory 1GB KIT (2 x 512MB) SO-DIMM DDR NON-ECC PC2100 266MHz 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)