4GB Total. 2 x 2GB 2048MB PC2-6400 200 pin SODIMM DDR2 800MHz 1.8v Low Density Non Parity Non ECC for Laptops Notebooks Netbooks Major Brand Industry Standard Memory such as Hynix, Samsung etc. Will work in all brand name laptops such as Acer, Apple, Dell, Gateway, HP, Lenovo, Sony, Toshiba etc CAUTION: PLEASE MAKE SURE THAT THIS IS THE RIGHT MEMORY FOR YOUR LAPTOP. SEND US A MESSAGE IF YOU ARE NOT SURE - WE WILL CHECK AND LET YOU KNOW. USED. TESTED. We do not sell OEM memory which may be unstable or prone to early failure. Warranty: 90 days Support: Contact us through eBay Memory expert since 1990. All parts are tested and guaranteed compatible. No hassle exchanges. Brand name parts only- No unknown and overclocked parts. Quick shipping. Guaranteed and tested. 100% compatible with all devices which take this type of memory.