SAMSUNG M471A1K43CB1-CTD 8GB DDR4 2666MHz - Memory Modules (1 x 8GB, 2666 MHz, 260-Pin SO-DIMM, Black, Green) at Amazon.com
Crucial 8GB 260-Pin DDR4 SO-DIMM DDR4 2666 (PC4 21300) Memory for Apple Model CT8G4S266M - Newegg.com
Best Notebooks Ramaxel RMSA3260ME78HAF-2666 8gb Pc4 2666MHz DDR4 So-Dimm Non-ECC 260 pin 1.2V Ram Memory for Laptop and All in One Desktop Computer ( 8gb Pc4 2666MHz DDR4 So-Dimm) at Amazon.com