HDD WD 2.5" 500GB  BLUE 5400RPM SATA 128MB 

HDD WD 6TB NAS Red Plus SATA3(6Gb/s) 128MB 5640RPM

HDD WD 3.5" 6TB BLUE 5400RPM SATA Cache 256MB

12TB Storage Capacity , 3.5" Form Factor , SATA III 6 Gb/s Interface , 256MB Cache , 7200 rpm , Up to 240 MB/s Sustained Transfer Rate , 1 Million Hours MTBF , 180TB Yearly Workload Rating , Air Sealed

WD My Book 2017  4TB USB3.0

8TB Storage Capacity , 3.5" Form Factor , SATA III 6 Gb/s Interface , 256MB Cache , 5400 rpm , Up to 202 MB/s Sustained Transfer Rate , 1 Million Hours MTBF , 180TB Yearly Workload Rating , Air Sealed

WD My Book 2017  6TB USB3.0

6TB Storage Capacity , 3.5" Form Factor , SATA III 6 Gb/s Interface , 256MB Cache , 5400 rpm , Up to 202 MB/s Sustained Transfer Rate , 1 Million Hours MTBF , 180TB Yearly Workload Rating , Air Sealed

WD My Book 2017 8TB USB3.0

4TB Storage Capacity , 3.5" Form Factor , SATA III 6 Gb/s Interface , 256MB Cache , 5400 rpm , Up to 202 MB/s Sustained Transfer Rate , 1 Million Hours MTBF , 180TB Yearly Workload Rating , Air Sealed

WD My Book 2017 14TB USB3.0

16TB Storage Capacity , 3.5" Form Factor , SAS-3 12 Gb/s Interface , 512MB Cache , 7200 rpm , Up to 262 MB/s Sustained Transfer Rate , 2.5 Million Hours MTBF , 550TB /jo Yearly Workload Rating