Tire tread
Summer tires
Do not drive with a tire tread depth of less than 0.12 in/3 mm.
There is an increased danger of hydroplaning if the tread depth is less than 0.12 in/3 mm.
Winter tires
Do not drive with a tire tread depth of less than 0.16 in/4 mm.
Below a tread depth of 0.16 in/4 mm, tires are less suitable for winter operation.
Minimum tread depth

Wear indicators are distributed around the tire's circumference and have the legally required minimum height of 0.063 in/1.6 mm.
They are marked on the side of the tire with TWI, Tread Wear Indicator.
See also:
Capacities
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Display
Display
1. The system is activated.
2. Arrows: at least one lane marking was detected
and warnings can be issued. ...
BMW 7 Series Owners Manual
h4 {color:#800000}
h3 {color:#0033CC}
h2 {color:#008000}
h1 {color:#FF0000}
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