255/60 R17 doesn't belong to the most popular dimensions for allround 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 (255mm), which means the sidewall height has 153 mm. The wheel diameter is R17, which means it fits to a 17 inch/431.8mm diameter wheel. The total circumference of the tyre is 2317.87 mm, which is very similar to 255/65 R16(2318.18 mm), 255/55 R18(2317.55 mm), 255/50 R19(2317.24 mm), 255/70 R15(2318.5 mm), 255/45 R20(2316.92 mm), 255/40 R21(2316.61 mm), 235/65 R17(2316.3 mm). There are multiple speed indexes available for allround tyres in 255/60 R17: H(210km/h), V(240km/h). The same goes for weight indexes: 106.