Tread Depth, Measuring
When measuring tread depth, take measurements in the main grooves.
Do not measure on the TWI (tread wear indicator).
Tread depth of a tire must be measured in the main grooves at the points showing the most wear. Main tread grooves can be recognized by the TWI. The positions of the tread wear indicators are visible several times along the tire shoulder. The TWI protrusions are 1.6 mm tall. This is the minimum tread depth legally prescribed in Germany.
Different values may apply in other countries.
Tread Wear Indicators (TWI) must not be included in the measurement. The deepest point of the groove must be used for the measurement.
A - Tread wear indicators (TWIs) in main tread grooves. Items can be identified six times on the circumference of the tire shoulder.
B - Tread depth -P- in the main tread groove.
Tread wear indicators - TWI
Tread Wear Indicator means profile wear display
TWI TREAD DEPTH, MEASURING is visible six times on the circumference of the tire shoulder.