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 mainly collaborate with professional organizations certified by China's national CMA (Certification of Inspection and Testing Institutions). If you need the highest level of international endorsement, we can arrange for independent inspection agencies like SGS or TÜV to conduct Pre-Shipment Inspections (PSI) before loading at the port.

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.