Concealed coloured rubber stripe to indicate tyre tread wear - which becomes increasingly exposed after an initial wear limit

摘要

A car tyre tread incorporates a band of rubber of contrasting colour at a depth which is exposed when the tread is worn down towards its safe working limit, typically by 5-7 mm. The indicator band is of the same material quality as the rest of the (black) tread rubber, except for the colour of e.g. white, yellow or red. Pref. the indicator stripe has a divergeant cross section which becomes increasingly noticeable with further tyre wear.