Designed as an expedition sleeping bag for high-altitude trips, the The North Face Solar Flare boasts an extremely warm temperature rating of -18 deg C. More importantly though it also uses trapezoidal baffles for the ultimate in construction methods, so that cold spots are reduced to a minimum. The shell is made from waterproof and breathable Hyvent fabric to help keep the down dry.
The Solar Flare boasts a set of unique features to make it comfortable even in the worst of winter weather. The bag has synthetic panels of Climashield Prism insulation within compression zones down the back of the bag, so that these areas are not compressed, resulting in an improvement in warmth while improving efficiency by 13 per cent according to the manufacturer. The body of the bag has trapezoidal baffles, box wall baffles on the sides and there are seven baffles in the hood, which all adds up to controlled distribution of that precious down insulation. The foot box is enlarged, with a taper for a better fit, and there is a huge plug of down in the foot too for extra warmth around your toes. The side zip extends almost to the foot and is protected by a massive and well-filled draught collar to prevent cold spots. Also there is a shoulder baffle too, which is again wide and well stuffed with down. All that is packed into a waterproof shell so that the insulation’s efficiency is not compromised by dampness.
On the hill
The bag comes with a compression stuffsack that allows its relatively high bulk to be easily cranked down. The first thing I noticed when using this high on Glaramara was the foot shape, as my size 11 feet did not squash down the insulation. As this is a very warm bag, I was soon opening the zip for more air. It was noticeable how easily it slipped up and down without snagging and jamming, which is just what you want. It would be nice if that zip extended a little further to the foot, as I found my feet cooking at times, however usually your feet will need all the insulation they can get in the depths of winter. I particular liked the hood and shoulder baffle, which fitted well and were easy to adjust thanks to three different cord sizes that I could adjust in the dark. The shell is made of waterproof fabric, but the seams are not taped, and I found the down did get wet from a puddle of condensation in my tent.
Size 230x80x50cm long (medium also available)
Fill weight 1040g
Fill power 800 (US)
Comfort temperature rating -18 deg C
Packed size 32x27cm compressed
Weight of bag 1915g
Made in China
Stores in the UK 2
Stockist details tel. (01539) 738882; www.thenorthface.com/eu
Verdict: The North Face’s Solar Flare is a very warm sleeping bag that is ideal for the coldest of temperatures but price, weight and lack of waterproofness are drawbacks.