Apple PowerBook (3400 series) - Manual (Page 169)

If the keyboard cables are loose, follow these steps to replace the cables:
1 Lift the bail on the connector with a straightened paper clip or similar object.
2 Insert the ribbon cable into the connector.
3 Push down on the bail with a straightened paper clip or similar object
to secure the ribbon cable.
Bail
1 2 3
169 Installing a Macintosh PowerBook RAM Expansion Card