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Other World Computing - DDR3 - kit - 8 GB: 2 x 4 GB - SO-DIMM 204-pin - 1333 MHz / PC3-10600 - CL9 - 1.5 V - unbuffered - non-ECC - for Apple iMac; Mac mini (Mid 2011); MacBook Pro (Early 2011, Late 2011) - Walmart.com
Amazon.com: 4GB DDR3-1066 (PC3-8500) RAM Memory Upgrade for The Apple MacBook Pro 13.3" Core 2 Duo 2.40GHz 250GB 13.3 2.4GHz 250GB (Z0J7-2.4-8GB-250GB) : Electronics
Amazon.com: Apple 13.3" MacBook Pro w/ Touch Bar (Mid 2018), 227ppi Retina Display, Intel Core i5-8259U Quad-Core, 256GB PCI-E Solid State Drive, 8GB DDR3, 802.11ac, Bluetooth, macOS 10.13, Space Gray (Renewed) :
CMS 16GB (4X4GB) DDR3 8500 1066MHZ ECC Non Registered DIMM Memory Ram Compatible with Apple Mac Pro 2.26Ghz 8-Core Xeon MB535Ll/A - B130 at Amazon .com