For sale is a USED Cisco QNAP TS-659 Pro+ 6 Bay 
Network Attached Storage (24TB total)

This Cisco-branded QNAP TS-569 NAS supports up to 6 HDDs and has a current storage capacity of 24TB using Samsung 2TB Drives. It is powered by an Intel Atom D525 processor and has 2x Ethernet interface for network connectivity. This QNAP model is ideal for home or office use, and its 6 bays provide ample storage space for all your data needs. The device supports HDDs and is easy to set up and use. Whether you need to store important documents, media files, or backups, this QNAP TS-659 Pro+ NAS is a reliable and efficient solution.

https://www.qnap.com/en/product/ts-659%20pro/specs/hardware

I'm only selling as I'm trying to downsize my home.  It's a great a home NAS and personal cloud for backing up lots of photos, video, files, etc.  I have another one with 6x42TB (12TB total) drives if you want to synchronise them at two locations for additional redundancy.
  • As seen in photos (Cisco branded QNAP TS-659)
  • Factory Reset, latest firmware (see pictures)
  • All drives are showing as Healthy (see pictures)
  • UK Power Cable included
CPUIntel® Atom™ Dual-core Processor
DRAM1GB DDRII RAM
Flash Memory512MB DOM
HDD6 x 2.5"/3.5" SATA
NOTE:
  1. The system is shipped without HDD.
HDD Tray6 x Hot-swappable and lockable tray
LAN Port2 x Gigabit RJ-45 Ethernet port
LED IndicatorsStatus, LAN, USB, eSATA, Power, HDD 1, HDD 2, HDD 3, HDD 4, HDD 5, HDD 6
USB5 x USB 2.0 port (Front: 1; Back: 4)
Support USB printer, pen drive, USB hub, and USB UPS etc.
eSATA2 x eSATA port (Back)
ButtonsSystem: Power button, USB One-Touch-Backup Button, Reset button
LCD panelMono-LCD display with backlight
Enter button, Select button for configuration
Alarm BuzzerSystem warning
Form FactorTower
Dimensions175 (H) x 257 (W) x 235 (D) mm
6.89 (H) x 10.12 (W) x 9.25 (D) inch
WeightNet weight: 5.2 kg (11.46 lbs)
Gross weight: 6.5 kg (14.33 lbs)
Sound Level (dB)w/o HDD installed: 35.7 dB
Stand by: 35.2 dB
In operation: 40.8 dB
(with 6 x 500GB HDD installed)
Power Consumption (W)Sleep mode: 22W
In Operation: 43W
Power-off (in WOL mode): 1W
(with 6 x 500GB HDD installed)
Temperature0~40˚C
Humidity0~95% R.H.
Power SupplyInput: 100-240V AC, 50/60Hz, Output: 250W
Secure DesignK-lock security slot for theft prevention
VGAReserved VGA interface for maintenance
Fan2 x quiet cooling fan (9 cm, 12V DC)

Advanced RAID Management with Hot-swap Design
The NAS offers RAID 0, 1, 5, 5+spare, 6, 6+spare, 10, 10+spare, single, and JBOD disk configurations. It also supports hot-swap design that a failed member drive of a RAID configuration (RAID 1 or above only) can be replaced by hot swapping without turning off the server.