Allied Telesis AT-SBx81CFC960 - Manual (Page 244)

Chapter 12: Replacing Modules
244 Section II: Installing the Chassis
Figure 165. Reinstalling the Nut and Washer on the Grounding Post
11. Lift the locking handle and slide the power supply from the chassis.
Refer to Figure 166 on page 245.
Warning
The power supply is heavy. Use both hands to hold the module as
you remove it from the chassis.