Allied Telesis AT-SBx31CFC960 - Manual (Page 256)

Chapter 13: Replacing Modules
256
Figure 157. Lifting the Locking Handle on the Power Supply
3. Carefully pull on the locking handle to slide the power supply from the
chassis. Refer to Figure 158 on page 257.
Warning
The power supply is heavy. Use both hands to hold the module as
you remove it from the chassis.