Checkpoint: 1.3 x 1.6 inches (33 x 41 mm) Pack of 10 for checking the looseness of the nut caused by vibration and impact when driving. The accident of dropping the wheel of large cars is increasing in recent years. One reason is due to loosening wheel nuts. Even if you have tested before operation with safety care, the wheel nut is undetectable. Not all tire foils associated with accidents are prevented, but please use it as a safety precaution.