A good baselayer will make a world of difference especially when undertaking physical activity outdoors in colder climates. Most people think of baselayers as something you wear under a ski jacket once a year but a baselayer should be a consideration when you're spending any length of time outdoors. As with most things, the type of baselayer you need will largely depend on what you're going to be doing in it. If it's likely that you'll need to be able to quickly regulate your temperature in changeable weather then look for a baselayer with a chest zip for example. We have a great selection of Arc'teryx baselayers including short and long sleeve, zipped and non-zipped and all made from top quality materials designed to retain warmth while wicking away moisture. If you're looking to build an effective layering system then why not compliment your Arc'teryx baselayer with an Arc'teryx fleece or midlayer.