235/60 R20 doesn't belong to the most popular dimensions for summer tyres - there are 1 tyre models available, which can be compared to
155/60 R15,
170/60 R17,
160/60 R14. Let's break down the sizing - 60 is height of the tyre, which is calculated as 60% of the tyre width (235mm), which means the sidewall height has 141 mm. The wheel diameter is R20, which means it fits to a 20 inch/508mm diameter wheel. The total circumference of the tyre is 2481.86 mm, which is very similar to 285/45 R21
(2481.54 mm), 275/65 R17
(2479.66 mm), 275/70 R16
(2486.26 mm), 255/55 R20
(2477.15 mm), 285/50 R20
(2491.28 mm), 285/40 R22
(2471.81 mm), 315/40 R21
(2467.41 mm). There are multiple speed indexes available for summer tyres in 235/60 R20: H
(210km/h), W
(270km/h). The same goes for weight indexes: 108.