External Rolling Noise - Ferrari 488GT Owner's Manual

External rolling noise

1
The bottom of the label indicates the external noise level of the
tyre. The external noise level is measured in decibels (dB) and is
divided into 3 categories based on the new, stricter European levels
of external tyre noise which will be introduced by 2016.
1 black sound wave: 3 dB below future European limit.
2 black sound waves: complies with future European limit.
3 black sound waves: complies with current European limit.
General
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