Crucial Pro RAM 32GB Kit (2x16GB) DDR4 3200MT/s (or 3000MT/s or 2666MT/s) Desktop Memory CP2K16G4DFRA32A at Amazon.com
G.SKILL F4-3600C16Q-32GTZR 32 GB (8 GB x 4) Trident Z RGB Series DDR4 3600 MHz Dual Channel Memory Kit - Black with Full Length RGB LED Light bar at Amazon.com
Best Buy: CORSAIR Vengeance RGB PRO 32GB (2PK 16GB) 3GHz PC4-24000 DDR4 DIMM Unbuffered Non-ECC Desktop Memory Kit with RGB Lighting Black CMW32GX4M2C3000C15
Crucial 32GB 2 x 16GB DDR4 SDRAM Memory Kit For iMac 32 GB 2 x 16GB DDR4 2666PC4 21300 DDR4 SDRAM 2666 MHz CL19 1.20 V Non ECC Unbuffered 260 pin SoDIMM - Office Depot
32GB Memory Upgrade for 2019-2020 iMac and 2018 Mac mini