APC AP9254 - Manual (Page 7)

The APC KVM Switch requires a PS/2 mouse and keyboard. The
following mice are known to be compatible:
IBM PS/2-style Logitech Trackman
Kensington Microsoft Serial-PS/2 mouse
Logitech Mouseman (PS/2) Microsoft IntelliMouse
Other manufacturers' mice may operate with the APC KVM Switch. If
you experience problems using an untested mouse, contact APC
Technical Support with the manufacturer and model number of the
mouse in question.
1.2 Compatibility
3