Apple PowerBook 165 - Manual (Page 140)

Upgrades Modem Card - 2
Caution:
If you install a
third-party modem card,
make sure that it does not
cover any of the heat sinks
on the daughterboard or over
the floppy drive.
Note:
The modem card is an
option for the PowerBook
160/165/180.
1 Pinch the release tabs
and push out the modem
port cover.
Modem Port Cover
Release
Tabs