CyberData 10935 Operation Manual page 83

If the thread on the conduit is longer than 3/8 inch, then a stop nut (not supplied) is required.
Otherwise, use the outlet box plug to plug the exit hole.
Note
Figure A-4
Not to Exceed 0.1"
Operations Guide
Apply good quality waterproof sealant to all threads.
Figure A-3. Mounting the VoIP Intercom Assembly
shows the restrictions of the conduit going into the box.
Figure A-4. Conduit Restrictions
930242A-D
Apply good quality waterproof
sealant to all threads.
HOLE PLUG
OR
CONDUIT
CONDUIT (1/2")
CyberData Corporation
77
Mount the Intercom