Winter tyres tyre width 245 mm tyre cross section 50 rim diameter 18 inch load index 104 up to 900 kg speed rating v up to 149 mph installation all round tyre rolling resistance c wet grip b noise emission 70 db noise classification nc 2 runflat rim protector sipes symmetrical tread directional tread self sealing tyre runflat identification rof goodyear run flat technology rof runonflat rim protection marking fp mfs fr fl fsl