661-5002 1 GB, DDR3 1066, UDimm, ECC - Mac Pro Early 2009 A1289 NB-2215W This is 1GB DDR3 PC3-8500 RAM upgrade for the Mac Pro. This is for PC3-8500 DDR3 Machines. These are DIMM chips and not SODIMM chips used in MacBooks and iMacs. Apple part number: 661-5002