4GB KIT (2 x 2GB) For IBM-Lenovo System Series x3105 (4347-xxx) x3200 (4362-xxx) x3200 M2 (4367-xxx) x3200 M2 (4368-xxx) x3250 (4364-xxx) x3250 (4365-xxx) x3250 M2 (4190-xxx) x3250 M2 (4191-xxx) x3250 M2 (4194-xxx) x3350 (4192-xxx) x3350 (4193-xxx). DIMM DDR2 ECC Unbuffered PC2-6400 800MHz RAM Memory. Genuine A-Tech Brand. 4GB KIT (2 x 2GB) DIMM DDR2 ECC Unbuffered PC2-6400 800MHz RAM Memory Genuine A-Tech Memory Lifetime Warranty Toll Free Technical Support 1-866-557-4527 Designed For IBM-Lenovo System Series. (See Compatibility List Below)