Apple Macintosh Performa 6360 Series - Manual (Page 143)

4 Check the external connector on your card, see which of the following two illustrations
matches the card you have, and install the card according to the illustration.
If the card has a hook, make sure it engages the vertical plate before pushing
the card into the slot.
If the card does not have a hook, simply pass the external connector
through the opening in the vertical plate as shown. (Some cards have a
flat external connector.)
Communication slot
Vertical plate
External connector
Communication
card access hole
Communication slot
Vertical plate
Hook
Communication
card access hole
143 Installing Expansion Cards or Additional Memory