Lexus GX470 2004 Owner's Manual page 30

D Do not bend the key grip or flat key.
D Do not cover the key grip or flat key with any material
that cuts off electromagnetic waves.
D Do not knock the key or flat key hard against other
objects.
D Do not leave the key or flat key exposed to high
temperatures for a long period, such as on the
dashboard or hood under direct sunlight.
D Do not put the key or flat key in water or wash it in an
ultrasonic washer.
D Do not use the key or flat key with electromagnetic
materials.
KEYS AND DOORS
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