Laptop Macbook Pro 8.1 Late 2011 (A1278) Ram 2x4GB (total 8GB) DDR3 1333MHz PC3-10600 2Rx8 1.5V SODIMM, Computers & Tech, Parts & Accessories, Computer Parts on Carousell
How to Upgrade MacBook Pro RAM (2009, 2010, 2011, 2012): EveryMac.com
NEMIX RAM Compatible for 128GB (4x32GB) DDR4 2666MHz PC4-21300 SODIMM Memory Upgrade for Apple iMac Mid 2020 (iMac 20,1/20,2) / Mid 2019 (iMac19,1) 27-inch w/Retina 5K, Late 2018 Mac Mini 8,1 at Amazon.com
Upgrade MacBook Pro 8,1 to macOS Catalina with 16 GB of RAM – Jaehoo Weblog
Timetec 8GB KIT(2x4GB) Compatible for Apple DDR3L 1600MHz for Mac Book Pro (Early/Late 2011,Mid 2012), iMac(Mid 2011,Late 2012,Early/Late 2013,Late 2014,Mid 2015), Mac Mini(Mid 2011,Late 2012) MAC RAM at Amazon.com