Continental SportContact 6 is a summer tyre made in total of 195 sizes, ranging from R18 to R18 - this particular dimension is R20, which means it fits to a 20 inch/508mm diameter wheel. 305/30 R20 is 70mm wider than the narrowest dimension (235) and -10mm narrower than the widest one (295). This tyre profile of 30 means the sidewall height of the tyre is 30% of the tyre width (305mm), which results in 91.5mm sidewall height. In 305/30 R20, there is only one possible speed index for Continental SportContact 6 - "Y", which is good for speeds up to 300 km/h. In 305/30 R20, SportContact 6 usually competes against Ventus S1 evo3 K127, which is a tyre from Hankook with a rating of 74%, compared to 77% of the Continental in question.