First OptiNAND-based WD HDDs go on sale. 20 TB without SMR - HWCooling.net
Seagate confirms 20TB HAMR hard disk drives have been shipped | TechRadar
WP Arsenal 20TB SATA 6Gb/s 7200RPM 3.5" DAS HDD – Water Panther
Seagate's 20 TB hard drives ship | TechTarget
Amazon.com: WD Ultrastar DC HC560 WUH722020ALE6L4 20 TB Hard Drive - 3.5 Internal - SATA [SATA/600] - Conventional Magnetic Recording [CMR] Method,Mechanical Hard Disk : Electronics