Bottom
Component Description
(1)   Battery release latch Releases the battery.
(2)   Battery bay Holds the battery.
(3)   SIM slot
NOTE: Select Windows models only.
Supports a wireless subscriber identity module (SIM). The SIM slot is 
located inside the battery bay.
(4)   Docking connector Connects an optional docking device.
(5)   Accessory battery connector Connects an optional accessory battery.
(6)   Service door release lock Locks service door.
(7)   Service door release latch  Releases the service door on the computer.
(8)   Vents (3) Enable airflow to cool internal components.
NOTE: The computer fan starts up automatically to cool internal 
components and prevent overheating. It is normal for the internal 
fan to cycle on and off during routine operation.
(9)   Service door Provides access to the hard drive bay, the wireless LAN (WLAN) 
module slot, the WWAN module slot, and the memory module slots.
Bottom 17