CUMULUS Quilt 450CUMULUS Quilt 450 is suitable for use at temperatures slightly below zero. Quilt 450, combined with a good mattress is a little bit more thermally efficient than model Panyam 450 because the same amount of down fills a slightly smaller space. The quilt does not have a hood and is also a few inches shorter but most importantly, a much larger percentage of down filling is continuously used for insulation. Just as in other products of this series,