SAMSUNG M471A1K43CB1-CTD 2666MHz Memory Modules (8GB, 1 x 8GB, DDR4, 2666 MHz, 260-Pin SO-DIMM, Black, Green) at Amazon.com
Kimtigo DDR4 16GB Laptop Dram 2666MHz (PC4-21300) CL19 (Compatible with 2400MHz or 2133MHz) 1.2V Notebook (SODIMM) RAM Non-ECC Unbuffered Single Rank 260 Pin PC Computer Memory Module Upgrade at Amazon.com