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4 x 4GB (16.0GB), 1333MHZ, DDR3 SO-DIMM, PC3-10600, 204 Pin, 1.5V, 128Meg x 8, Non ECC, Dual Rank, Non Parity, Memory Upgrade Kit Memory Upgrade Module For iMac
Memory Upgrade KIt For Mid 2010/2011 21.5inch and 27inch iMac Models and PC Laptops compatible with Intel / AMD
Compatible with 27inch iMac Models: Mid 2011 iMac Model ID: iMac12,2 and Mid 2010 iMac Model ID: iMac11,3
Compatible with 21.5inch iMac Models: Mid 2011 iMac Model ID: iMac12,1 and Mid 2010 iMac Model ID: iMac11,2
OWC Memory Lifetime Limited Warranty including the OWC Lifetime Advanced Replacement Program