160/60 R18 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 (160mm), which means the sidewall height has 96 mm. The wheel diameter is R18, which means it fits to a 18 inch/457.2mm diameter wheel. The total circumference of the tyre is 2039.52 mm, which is very similar to 235/30 R20(2038.89 mm), 275/35 R18(2041.09 mm), 285/25 R20(2043.61 mm), 180/60 R17(2035.12 mm), 215/45 R18(2044.23 mm), 275/30 R19(2034.5 mm), 205/65 R15(2034.18 mm). There are multiple speed indexes available for allround tyres in 160/60 R18: W(270km/h). The same goes for weight indexes: 70.