Ricoh Di-C1 Manual page 142

Drum
Development
Roller
One PCDU for each colour.
The drum units are identical and can be interchanged. But the
development units cannot (they already contain developer).
Four colours are developed at the same time.
Slide 142
This shows the most important components of the PCDU.
The image transfer roller (not shown here) pulls the toner off the drum and
onto the transfer belt.
Overview
142
Di-C1 Training
Cleaning
Brush
Cleaning
Blade
Charge Roller