Vu+ Zero 4K has one Accessories Plug which support External HDD.
You can Sold separately purchase Accessories Plug.
A) Open the docking station.
B) Insert 2.5" HDD.
C) Screw up A point on the back of the PCB.
D) Put the PCB Combined with the HDD into the Plug(accessory).
E) Place the docking station up. Screw up B Point.
F) Combined the connector into the C point located on the Plug(accessory) docking station.
G) Combined the connector into the D point located on the bottom of the Zero 4K.