Premium materials, a tapered fit and box-wall construction makes this bag highly thermally efficient – a winner for winter camping.
Down fill not hydrophobic
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Mountain Hardwear Phantom 0/-18 is the flagship sleeping bag in the Mountain Hardwear line. As it's name suggests, the Phantom 0 offers warmth down to a bone-chilling -18°C. Yet, given its four-season capabilities, it is lightweight and compact, with an impressively small pack size that ranks among the best in this class. It is filled with a hefty 850g/1lb 14oz of 850 fill power down, housed in either a Pertex Quantum or Gore-Tex Windstopper fabric shell.
The fit is highly tapered to maximise thermal efficiency. As such some might find it a little restrictive, though at high altitudes or low temperatures you’ll appreciate the extra warmth.
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The one rather surprising omission is that the down fill has no hydrophobic treatment, though arguably the highly water-resistant outer renders this unnecessary.
• RRP: $760 (US)/£570 (UK)
• Weight: 1kg 208g/2lb 10.6 oz
• Length: 218cm/86in (regular), 234cm/92in (long)
• Max user height: 205cm/6ft 5in (regular), 220cm/7ft+ (large)
• Pack size: 21x42cm/8.25x16.5in
• Fill: 850-fill goose down
• Comfort limit: -7°C/19.4°F
• Limit: -18°C/0.4°F
In the field
In full winter conditions, being zipped up in this bag as your breath condenses in the chill air of your tent is a wonderful sensation. It does a great job of locking in vital warmth thanks to a well-designed neck baffle and vertical box-wall chest baffles to counter down migration, which could otherwise cause cold spots.
The footbox and panelled hood are similarly well-constructed. To be honest, there’s little to fault. So if you’re a serious winter camper, you might consider this tried-and-tested four-season down bag for your next adventure.
Similarly, if you’re heading off on a trekking or mountaineering expedition at higher altitudes, it’s a good choice to take with you. Otherwise, in all honesty there’s a good chance that a bag delivering this much warmth will be overkill.
An outdoors writer and editor, Matt Jones has been testing kit in the field for nearly a decade. Having worked for both the Ramblers and the Scouts, he knows one or two things about walking and camping, and loves all things adventure, particularly long-distance backpacking, wild camping and climbing mountains – especially in Wales. He’s based in Snowdonia and last year thru-hiked the Cambrian Way, which runs for 298 miles from Cardiff to Conwy, with a total ascent of 73,700 feet – that’s nearly 2½ times the height of Everest. Follow Matt on Instagram and Twitter.