Therm-a-Rest Saros™ 20F/-6C Sleeping Bag

The Saros 20F/-6C is a three-season synthetic mummy bag with a 950 g eraLoft fill, rated to 0°C comfort and -6°C limit under EN ISO 23537. Compared with down bags in a similar temperature bracket it's noticeably heavier at 1270 g total, but synthetic fill retains its insulating properties when damp and dries faster, which matters on wet treks or in humid climates. The 20D polyester shell with DWR treatment and 20D polyester taffeta liner are standard for the line, and a full-length zipper allows more ventilation range than the shorter zips on some siblings. A draft collar and draft tube reduce heat loss around the zipper, and SynergyLink loops anchor the bag to a sleeping pad. Packed size of 24 × 27 cm is bulkier than comparable down models — a typical trade-off of synthetic insulation. A maximum user height of 168 cm points to a shorter cut, so it's worth checking sizing before buying. Both a compression sack and storage sack are included.