PRESONUS NSB Series Owner's Manual page 35

To remove and relocate the rack ears:
1. Loosen and remove the six screws on each side of the NSB 32.16 using a hex driver (not included.)
2. Re-position the ears to the desired configuration.
For a recessed configuration, attach the back end of the rack ears to the frontmost holes of the NSB
32.16.
4.5 Configurable Rack Ears (NSB 32.16 only)
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