Rab Mythic Ultra 360 Down Sleeping Bag (-8c)

With its world-first heat-reflective Thermo Ionic Lining Technology, the Mythic Ultra 360 delivers pioneering protection for those who need to make every gram count.

Weight : 645g / 23oz
Rab Sleep Limit : -8°C / 18°F
Packed Size : 36 X 18cm / 14.2 X 7.1in


We recommend using this for:

  • Fast & Light Adventures
  • Mountaineering
  • Trekking

For mountain marathon runners and committed alpinists who need to travel light, the Mythic Ultra 360 is a game changer./

Built from lightweight recycled 10D Atmos™, it uses Thermo Ionic Lining Technology (TILT) to coat the fibres with titanium, helping reflect radiant heat back towards your body without compromising the fabric’s breathability. While that reduces the amount of down required for a given level of warmth, the angles of the bag’s trapezoidal boxwall construction also improve the evenness of down distribution, eliminating cold spots.

Filled in the UK with 900FP down and weighing in at just 645g, the Mythic Ultra 360 provides one of the most efficient warmth-to-weight ratios available.


  • Weight:Reg: 645g/22.7oz. XL: 706g/24.9oz
  • Insulation:900FP European Goose Down with Nikwax Fluorocarbon-Free Hydrophobic Finish (360g/12.07oz)
  • Main Fabric:10D Recycled Atmos™ (27gsm) with Fluorocarbon-Free DWR
  • Fabric Lining:10D Recycled Atmos™ (28gsm) with Thermo Ionic Lining Technology (TILT)
  • EN (13537:2012) Temperature rating:ISO EN: Comfort; -2°C ( 28°F), Limit; -8°C ( 18°F), Extreme; -27°C ( -17°F)
  • Rab Sleep Limit:-8°C / 18°F
  • Packed Size:36cm x 18cm (14.2in x 7.1in)
  • Product Code:QSI-43
  • Weight saving baffle construction, preventing down shift/migration
  • Trapezoidal boxwall construction, to maximise loft and warmth
  • Proportionally designed differential cut
  • Anti snag bonded zip guard
  • Ergonomically designed internal collar and hood
  • Angled foot box for relaxed sleeping posture
  • ½ length YKK® 3 coil main zip with noctilucent puller
  • Lightweight dry bag compression stuff sack

Material facts

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Material Facts

Mythic Ultra 360 Down Sleeping Bag (-8C)

Total Recycled Content*  41%
Fabric  99%
Outer 100%
Liner 99%
Hydrophobic Down 0%
Zips  35%
Trims  16%
Fluorocarbon Content 
Fabric  No
Outer No
Liner No
Hydrophobic Down No
Zips  Yes
Trims No
Manufactured in United Kingdom
*Calculations based upon the weight of a regular length sleeping bag.
QSI-43 Version 09/2023


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