All our measuring instruments (especially calipers, paint thickness gauges, and refrigerant pressure gauges) are calibrated quarterly according to ISO quality management system requirements to ensure the data we provide you is objective, accurate, and reliable.

We cannot open each tire to inspect the inside. However, if a visual inspection reveals severe creases on the tire sidewall, it indicates that the run-flat tire has been driven for a long time at zero pressure, damaging its internal structure. We would recommend replacing it before shipping.

Yes. For large B2B government or major fleet procurement projects, to ensure the safety of your deposit, we can issue an advance payment guarantee from one of China's four major state-owned banks, but the buyer must bear the issuance fee.