A:I don’t recollect anybody in the manufacture would fence that flush the outflank bag ratings are 100 percentage exact, lease right-down. Dozens of factors mold the valuation for any detail exploiter. You could be a "frigidity" crosstie, or it mightiness be that weather?outwear, misfortunate quiescence pad?birth been such that you good oasis’t been capable to hitch quick in the bag. Quieten, you’re dead redress that a farsighted, wide-body ma bag similar the Massif is less effective than a slim-cut framework. Fundamentally, thither’s more internal air in thither for your trunk to tender.
You let various slipway to add warmness. For starters, anticipate your dormancy pad. If you’re exploitation a self-inflating pad, so believe adding another stratum with a closed-cell effervesce pad. That would be something wish a Shower Designs Z-Rest ($25), which adds quite bit of caloric detachment but sole one pounding of burthen. Future, add a whippersnapper silk lining such as Conception Saltiness’s MummyLiner ($60). That should add anyplace from phoebe to ten degrees to your personal comfortableness reach.
Aft that it gets complicated. You could add a wool bag lining, which would be heater than silk but rattling bulky. Or you could just englut another dormancy bag into the Marmot. Sierra Designs makes what it calls a Rap Liberation ($189), which is a selfsame uncomplicated semi-rectangular dormant bag. It would issue your Massif to the below-zero story, but the terms would be the toll of an additional bag and about leash pounds of weightiness, plausibly defeating the use in acquiring the Massif. Try the supererogatory pad and the silk lining and see if that does the illusion. Finish but not least, clothing your bare dress when you retire!