Ricoh M281 Series Service Manual page 164

DataOverwriteSecurity Unit Type M19 (D3BS-03) (MP 501/601 Only)
4. Release the hook by opening the right side of the cover, and then remove the cover [A]
by rotating it in the direction of the blue arrow.

Be careful not to damage the hooks on the inside of the controller cover when you
remove or install the controller cover.
5. Insert the DataOverwriteSecurity Unit Type M19 SD card in SD Card Slot 1 [A] (upper
slot).
D255/D256/M281/M282 2-136 SM