本帖最后由 SheJing 于 2013-10-28 10:57 编辑 ; Z6 H5 m5 @0 J" k: ~) L/ a 8 i6 Y! `2 Y5 t4 \8 _9 i% h! H1 s6 u% XNot required by law. All major chained tire stores love to use it to rip people off. Go to smaller / individual tire shops or any mechanical shops.