Kingston Hyper X Blu 8 GB (2x4GB Modules) 1600MHz DDR3 Non-ECC CL9 XMP Desktop Memory - KHX1600C9D3B1K2/8GX at Amazon.com
Kingston Value (KVR16N11/8) RAM 8 GB 1600MHz DDR3 (PC3-12800) Non-ECC CL11 240 Pin DIMM Motherboard Memory at Amazon.com
G.Skill Ripjaws X Series 16 GB (2 x 8 GB) 240-Pin SDRAM (PC3-12800) DDR3 1600 CL10-10-10-30 1.50V Dual Channel Desktop Memory Model F3-12800CL10D-16GBXL at Amazon.com
Amazon.com: OWC 8GB (2 x 4GB) PC19200 DDR4 2400MHz SO-DIMMs Memory Compatible with Mac Mini (Late 2018), 27" and 21.5" iMac (Mid 2017), and Compatible PCs (OWC2400DDR4S08P) : Everything Else
4GB PC10600 DDR3 1333MHz SO-DIMM Memory Compatible with 2011 MacBook Pro, Mid 2010/2011 21.5" & 27" iMac Models, 2011 Mac Mini (OWC1333DDR3S4GB) at Amazon.com
G.Skill Ripjaws X Series 16 GB (2 x 8 GB) 240-Pin SDRAM (PC3-12800) DDR3 1600 CL10-10-10-30 1.50V Dual Channel Desktop Memory Model F3-12800CL10D-16GBXL at Amazon.com