4GB ( 1 x 4GB Module ) DDR2 800 MHz ( PC2-6400 ) DDR2 SO-DIMM ( 200-Pin ) Non-ECC Unbuffered Apple Mac Certified Memory RAM Upgrade Designed For Select Apple Mac Systems: MacBook, iMac (for a complete list of compatible systems, see the description section) Compatible Apple Order Numbers: MB323LL/A / MB324LL/A / MB325LL/A / MB398LL/A / MC240LL/A Compatible Apple Model IDs: iMac8,1 / MacBook5,2 Compatible Apple Model Numbers/EMC: A1181 (EMC 2330) / A1224 (EMC 2210) / A1225 (EMC 2211) A-Tech provides a Lifetime Warranty for all orders & offers complimentary United States based Tech Support before, during, & after your purchase