BenQ Z2 - Manual (Page 20)

4 Preparing Your Phone For Use
Placing the Back Cover
Align the tabs on the inside left edge of the back cover with the holes on
the left edge of the phone. Then place the back cover onto the phone's
back until the latch catches the cover.
Charging the Phone
1. Insert the charger connector deep into the charger socket at the left
side of the phone until the connector locks into place. Be sure that
the connector is inserted in the right direction (the side showing the
"UP"/arrow icon faces you).
Back cover latch