TECMIYO DDR3L 1600MHZ SODIMM RAM 4GB, DDR3 PC3L-12800S 204Pin Non ECC Unbuffered 1.35V/1.5V CL11 2RX8 Dual Rank for Laptop Notebook Computer Memory Module-Blue at Amazon.com
OWC 8GB (2 x 4GB) PC12800 DDR3L 1600MHz SO-DIMMs Memory Compatible with 2011-2015 iMac, 2011-12 Mac Mini, and 2011-2012 MacBook Pro (Non-Retina Display) Models (OWC1600DDR3S08S) at Amazon.com