Lenovo ThinkPad E550 User Manual page 59

Front view
1 Security-lock slot: To protect your dock from theft, you can purchase a security cable lock, such as
a Kensington-style cable lock, that fits this security-lock slot to lock your dock to a desk, table, or other
non-permanent fixture.
2 USB 3.0 connector: Used to connect devices that are compatible with USB 3.0 and USB 2.0.
3
Always On USB connector: By default, the Always On USB connector enables you to charge some
mobile digital devices and smartphones no matter when your computer is in sleep mode, hibernation mode,
or is off. For more information, refer to the documentation that comes with the dock.
4 Combo audio connector: Used to connect headphones or a headset that has a 3.5-mm (0.14-inch),
4-pole plug.
5 System-status indicator: The indicator on the illuminated ThinkPad logo functions the same as the ones
on the computer. For details, see "Status indicators" on page 9.
6 Power button: The power button on the dock functions the same as the one on the computer.
Rear view
.
Chapter 3 Enhancing your computer
43