4GB ( 1 x 4GB Module ) DDR3 1866/1867 MHz ( PC3-14900 ) DDR3 SO-DIMM ( 204-Pin ) Non-ECC Unbuffered Apple Mac Certified Memory RAM Upgrade Designed For Select Apple Mac Systems: iMac (for a complete list of compatible systems, see the description section) Compatible Apple Order Numbers: MK462LL/A / MK472LL/A / MK482LL/A Compatible Apple Model IDs: iMac17,1 Compatible Apple Model Numbers/EMC: A1419 (EMC 2834) A-Tech provides a Lifetime Warranty for all orders & offers complimentary United States based Tech Support before, during, & after your purchase