Laufenn Z Fit EQ LK03 is a tyre made in total of 44 sizes, ranging from R17 to R17 - this particular dimension is R20, which means it fits to a 20 inch/508mm diameter wheel. 285/30 R20 is 80mm wider than the narrowest dimension (205) and -20mm narrower than the widest one (265). This tyre profile of 30 means the sidewall height of the tyre is 30% of the tyre width (285mm), which results in 85.5mm sidewall height. In 285/30 R20, there is only one possible speed index for Laufenn Z Fit EQ LK03 - "Y", which is good for speeds up to 300 km/h.