HP ProBook 4520s Maintenance And Service Manual page 60

2. To remove the switch cover, remove the following:
(1) Two screw covers on the rear edge of the computer
(2) Two PM2.5×2.5 screws
(3) Three PM2.0×2.5 broadhead screws located in the battery bay
3. Open the computer as far as possible.
4. Slide the switch cover back (1), and then remove it from the computer (2).
52 Chapter 4 Removal and replacement procedures