GB/T 39971-2021 English PDF (GBT39971-2021)

This Standard specifies the thresholds and grading requirements and test methods for relative wet grip index for motor vehicle tyre. This Standard is applicable to new car radial tyres and new mini, light truck radial tyres and new truck radial tyres, excluding tyres with nominal rim diameter ??10 inches and nominal rim diameter ??25 inches, T-type spare tyres for temporary use only, special ST metric tyres for road trailers, high-passability radial tyres for light trucks, truck tyres with a speed capability of 80km/h (not included), racing tyres, studded tyres and professional off-road tyres.