16GB Memory for QNAP NAS TVS-873E Server DDR4 2400MHz RAM Module SO-DIMM (MemoryMasters) at Amazon.com
Amazon.com: Corsair CMY16GX3M2A2400C11R Vengeance Pro 16GB (2x8GB) DDR3 2400MHz PC3 19200 Desktop RAM, Red 1.65V : Cell Phones & Accessories
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
Crucial 16GB Single DDR4 2133 MT/s (PC4-17000) DR x8 SODIMM 260-Pin Memory - CT16G4SFD8213 at Amazon.com
Amazon.com: OWC 64GB (4 x 16GB) PC19200 DDR4 2400MHz SO-DIMMs Memory Compatible with 27" iMac (Mid 2017), and Compatible PCs (OWC2400DDR4S64S) : Everything Else
G.SKILL Ares Series 16GB (2 x 8GB) 240-Pin DDR3 SDRAM DDR3 2400 (PC3 19200) Desktop Memory Model F3-2400C11D-16GAB at Amazon.com
G.Skill 16GB (2 x 8GB) DDR3 PC3-19200 2400MHz TridentX Series CL10 (10-12-12-31) Dual Channel kit (F3-2400C10D-16GTX) at Amazon.com