185/45 R17 doesn't belong to the most popular dimensions for winter tyres - there are 0 tyre models available, which can be compared to 155/60 R15, 170/60 R17, 160/60 R14. Let's break down the sizing - 45 is height of the tyre, which is calculated as 45% of the tyre width (185mm), which means the sidewall height has 83.25 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 1879.61 mm, which is very similar to 215/45 R16(1884.64 mm), 185/65 R14(1872.7 mm), 175/70 R14(1886.84 mm), 205/40 R17(1871.76 mm), 195/55 R15(1870.82 mm), 165/65 R15(1870.82 mm), 195/50 R16(1889.35 mm).