Acer Aspire E1-521 Service Manual page 139

Attach the 21 screws to secure the upper case and the lower case.
5.
Install the keyboard (see
6.
Install the base door (see
7.
Screw Name
M 2.0 x 2.5
M 2.5 x 5.0
M 2.5 x 8.0
Service and Maintenance
Figure 5:55. Attaching the Upper and Lower Case Screws
Keyboard Installation
Base Door Installation
Table 5:6. Upper and Lower Case Screws
on page 5-32).
on page 5-13).
Screw Type Quantity
3
2
16
5-40