Amazon.com: OWC 32GB (2 x 16GB) PC19200 DDR4 2400MHz SO-DIMMs Memory Compatible with Mac Mini (Late 2018), 27" and 21.5" iMac (Mid 2017), and Compatible PCs (OWC2400DDR4S32P) : Everything Else
Upgrading RAM On The New 27-inch iMac Is Easy, Here's How | Cult of Mac
Apple Memory Module 16GB DDR4 2400MHz SO-DIMM (2x8GB) - Apple
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How to upgrade iMac (2020) RAM and save up to $2000 - 9to5Mac