Samsung 4GB DDR3 PC3-12800 1600MHz 204-Pin SODIMM Laptop Memory Module RAM. Model M471B5273DH0-CK0 at Amazon.com
DDR3 8 Gbit Components
OWC 16GB (2x8GB) ram Upgrade PC3-12800 DDR3L 1600MHz sodimm 204 Pin CL11 Memory Upgrade Kit Compatible with Late iMac, Mac Mini, and MacBook Pro Computer at Amazon.com
16GB (2x8GB) DDR3 1600MHz Non-ECC Memory Module | Integral Memory
Samsung Memory Ram Ddr3 2g 4g 8g 12800s Laptop Ddr3 1600 Mhz Memoria Dram Stick For Notebook Original 1.5v - Rams - AliExpress