The UltraGrip Performance 3 is one of the best tyres we have seen in the tests and on top of that it's top discipline is snow performance while maintaining great properties on wet, which makes it a great candidate for snowy climates.
265/65 R18 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 - 65 is height of the tyre, which is calculated as 65% of the tyre width (265mm), which means the sidewall height has 172.25 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 2518.61 mm, which is very similar to 285/65 R17(2520.5 mm), 265/70 R17(2522.07 mm), 265/75 R16(2525.53 mm), 285/60 R18(2510.76 mm), 235/85 R16(2531.81 mm), 285/50 R20(2491.28 mm), 275/70 R16(2486.26 mm). There are multiple speed indexes available for winter tyres in 265/65 R18: H(210km/h), R(170km/h), T(190km/h). The same goes for weight indexes: 114, 116.