Hello,.
We changed to Dunlops on delivery. They are only available through a Lexus Dealer, who swapped them as part of the deal. So glad we did as they are so quiet. The tyres are, Dunlop (Made in Japan) Size 225/50RF 18 95V SP SPORT MAX
Hope this helps
Paul
PS:- I spoke to Dunlop Technical who advised that these Run Flats can be repaired, with a patch, if punctured across the middle of the tread---which is good news. The Lexus parts dept also stated that they were not expensive at £95 each plus vat.plus fitting.