See also:

Treadwear
The treadwear grade is a comparative rating based on the wear rate of the tire when tested under controlled conditions on a specified government test course. For example, a tire graded 150 would we ...

Key lock-in prevention function
This function prevents the doors from being locked with the key still in the ignition switch. ...

Wear indicators
1) New tread 2) Worn tread 3) Tread wear indicator Each tire incorporates a tread wear indicator, which becomes visible when the depth of the tread grooves decreases to 0.063 in (1.6 mm). A tir ...