Toyota 2012 Matrix Owner's Manual page 288

3-6. Using the storage features
CAUTION
■
Caution while driving
Keep the auxiliary boxes closed.
Injuries may result in the event of an accident or sudden braking.
■
Items unsuitable for storing (overhead console only)
Do not store items heavier than 0.4 lb. (0.2 kg).
Doing so may cause the auxiliary box to open and the items inside may fall
out, resulting in an accident.
306
Auxiliary boxes