Winter tyres tyre width 295 mm tyre cross section 30 rim diameter 20 inch load index 101 up to 825 kg speed rating w up to 168 mph rolling resistance e wet grip c noise emission 75 db noise classification nc 2 runflat rim protector runflat identification ssr csr sst continental run flat technology ssr self supporting runflat tyre rim protection marking fp mfs fr fl fsl ml rpb