Ricoh M160 Service Manual page 658

Fax Unit Option
2. Remove the inquiry card from the handset cradle.
3. Fix the handset cradle to the handset bracket by turning the screws with a coin.
4. Place the inquiry card back on the handset cradle.
5. Place the handset on the handset cradle, and connect the handset cord to TEL.
SM 2 M160/M161 Fax Option