Generally speaking a 3mm or a 5mm glove will do the trick. It depends on the person for the most part though. I prefer a 3mm glove pretty much year-around. I´m plenty warm with them and have great dexterity for my camera or other items. I have friends who feel they are going to freeze to death through their hands if they go with anything less than 5mm. It all depends upon the person and their tolerance to cold.
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