190/50 R17 doesn't belong to the most popular dimensions for winter tyres - there are 17 tyre models available, which can be compared to 205/65 R15, 205/40 R18, 205/75 R16. Let's break down the sizing - 50 is height of the tyre, which is calculated as 50% of the tyre width (190mm), which means the sidewall height has 95 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 1953.44 mm, which is very similar to 185/65 R15(1952.5 mm), 205/40 R18(1951.56 mm), 195/55 R16(1950.61 mm), 235/40 R17(1947.16 mm), 160/60 R17(1959.73 mm), 215/45 R17(1964.44 mm), 205/60 R15(1969.78 mm). There are multiple speed indexes available for winter tyres in 190/50 R17: W(270km/h). The same goes for weight indexes: 73.