Lexus GS430 User Manual page 504

IN CASE OF AN EMERGENCY
G40004
2. Lift up the back side of the board and secure the
board by hooking the lever at the top of the trunk lid
opening as shown.
Make sure the board is secured and does not fall down.
480
G40005
When closing the board, replace the hook also in its
original position as shown.
NOTICE
If you close the trunk lid with the board hooked,
the hook may be damaged.