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Amazon.com: Crucial 8GB Kit (4GBx2) DDR3/DDR3L 1600 MT/s (PC3-12800) SODIMM 204-Pin Memory For Mac - CT2K4G3S160BM : Everything Else
OWC 8GB PC3-12800 DDR3L 1600MHz SO-DIMM 204 Pin CL11 Memory Module Upgrade Compatible with iMac, Mac Mini, and MacBook Pro (OWC1600DDR3S8GB) at Amazon .com
Ram Memory 8GB kit (2 x 4GB) DDR3 PC3-12800,1600MHz, 204 PIN SODIMM for laptops at Amazon.com