One option I was considering was getting an Alpkit Skyehigh 900 + Hunka XL + Thermarest NeoAir Xtreme + Alpkit Masson sleeping bag liner, would this work? It might seem overkill but I don't want to get cold or wet. Insulation is undoubtedly one of the biggest drivers in decisions regarding winter sleeping bags. It’s what the bag is made of, after all! And ultimately, you’ve got two options: down or synthetic. Snugpak’s polyester Softie insulation has been a mainstay in the British brand’s products for over thirty years. It utilizes superfine yarns bound together with special resins to mimic the properties of natural insulation such as down. The result is a really plush feeling bag that is easily warm enough for winter camping trips. As zips can allow for heat to escape, a good winter bag will also come with baffles along the length of the zip that seal everything in once it’s closed. A baffle will often be present around the shoulders to cinch down and tighten everything up, thereby preventing any heat from escaping through the night. Combine with a good sleep system Made for adventurers who won’t likely camp when it’s much below freezing, REI’s Down Time 25 has the bells and whistles to make sleeping out great, as well as a robust and verified eco story.

OEX Leviathan EV 900 sleeping bag sleeping bag review | Advnture

This bag is a gloriously cozy cocoon to nestle within and, with a comfort limit of -15°C (5°F), it is wonderfully toasty in all but the most Baltic conditions. However, it's limited to sub-zero use, as its elasticated expander panel allows the user to open things up, thus regulating the temperature inside. The Kelty Cosmic Down 20’s is unusual in that it uses trapezoid-shaped baffles to provide insulation. The dog approves (Image credit: Kelty) InsulationOne clear difference when it comes to 4-season bags is that they will almost always come with hoods and baffles. Rectangular bags that don’t cover your head might be fine during the warmer parts of the year, but in the winter you really need a bag in which you can properly batten down the hatches. That’s why winter bags almost always come with hoods that can be cinched down tightly around the head. OEX list this bag as having a comfort temperature of -9 degrees Celsius, a lower limit of -16 and an extreme rating of -39. They tested the bag according to EN13537 (which is an industry standard means of testing how warm sleeping bags are), and having used the bag for over three years, we definitely have some thoughts on these numbers (which we cover below). The OEX Leviathan EV 900 has an impressive comfort rating but we wouldn’t recommend bivying in it (Image credit: Craig Taylor) The Exped Waterbloc Pro sleeping bag is a 4-season sleeping bag designed with bivying in mind. It has 800 fill down, making it very soft and warm, with a Pertex outer shell that repels the weather.

Oex Leviathan EV 900 Sleeping Bag | GO Outdoors Oex Leviathan EV 900 Sleeping Bag | GO Outdoors

Made from extremely light and compressible Responsible Down Standard-certified insulation that’s been treated to repel water, this bag has several distinguishing features. For UK use, however, we think the bag delivers enough warmth to reasonably be considered a true 4-season sleeping bag, and we’re happy with its performance overall. We wouldn’t take it on a winter arctic expedition, but we’d be happy using this on practically any winter camping trip throughout the UK, and would only upgrade to something warmer if we were camping at elevation or in winter weather that’s uncharacteristically harsh (and cold) for the UK. Weighing 1,370g (3lb), the Leviathan 900 is also reasonably lightweight, considering the temperatures it is designed for. And while there are bags out there that will deliver an equivalent level of warmth at a fraction of the weight, there’s simply no beating it at this price point.Small: 10.6in x 6.7in / 27cm x 17cm; Medium: 10.6in x 6.7in / 27cm x 17cm; Large: 10.6in x 6.7in / 27cm x 17cm

OEX Leviathan EV 900 Sleeping Bag | Ultimate Outdoors OEX Leviathan EV 900 Sleeping Bag | Ultimate Outdoors

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