Apple Memory Module 16GB DDR4 2400MHz SO-DIMM (2x8GB) - Apple
iMac 24" with Retina 4.5K display All-In-One Apple M1 8GB Memory 256GB SSD w/Touch ID Silver MGPC3LL/A - Best Buy
Timetec 16GB KIT(2x8GB) 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
8GB vs 16GB for M1 Mac — The TRUTH About RAM! - YouTube