Oki C3400n User Manual page 92

drive gear into the gear inside the printer by the rear left corner
of the unit, and lower the belt unit flat inside the printer.
belt_roll in _ F5_09.jpg
8. Turn the two fasteners (1) 90° to the right until they lock. This
will secure the belt unit in place.
belt_lock_F5_09_1.jpg
9. Replace the 4 image drums, complete with their toner cartridges,
into the printer in the correct positions as shown.
C3400n User's Guide
92