345/30 R21 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 - 30 is height of the tyre, which is calculated as 30% of the tyre width (345mm), which means the sidewall height has 103.5 mm. The wheel diameter is R21, which means it fits to a 21 inch/533.4mm diameter wheel. The total circumference of the tyre is 2326.04 mm, which is very similar to 295/35 R21
(2324.46 mm), 235/55 R19
(2328.23 mm), 235/60 R18
(2322.27 mm), 285/45 R19
(2321.95 mm), 255/70 R15
(2318.5 mm), 255/65 R16
(2318.18 mm), 255/60 R17
(2317.87 mm). There are multiple speed indexes available for winter tyres in 345/30 R21: W
(270km/h). The same goes for weight indexes: 111.
