Xerox 665 System Administrator Manual page 309

WorkCentre Pro 665/685/765/785
To replace the Ozone Filter:
8. Remove the Ozone Filter from the inside of the machine. Then,
place the new ozone filter into the machine.
9. Close the Top Cover. Press down on the Top Cover until a "click"
is heard to ensure the latches engage.
Top Cover
Ozone Filter
077
101
B-19