Winter tyres tyre width 235 mm tyre cross section 40 rim diameter 18 inch load index 95 up to 690 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 runflat identification dsst dunlop run flat technology dsst dunlop self supporting technology rim protection marking fp mfs fr fl fs