Rab Mythic 600 Down Sleeping Bag (-12c)

Ultra-lightweight with a highly tapered cut, the Mythic 600 is designed for alpine style missions where weight and pack size are crucial to success. Filled with 900FP goose down and covered with a lightweight recycled Atmos™ fabric, it's a high-performance bag for those meticulously counting grams.

Weight : 925g / 33oz
Rab Sleep Limit : -12°C / 10°F
Packed Size : 41 x 22cm / 16.2 x 8.7in

The Mythic range is all about slashing weight wherever possible. The Mythic 600 is an extremely lightweight four-season bag. At home in high mountains, it’s ideal for venturing out long Alpine routes, multi-day climbs, treks, or bikepacking adventures.

Weighing in at just 925g, it contains 600g of 900FP goose down. The chevron style baffle design keeps the down in position, optimising core warmth and reducing the amount of fabric needed compared to traditional horizontal baffles. The outer is made from our own wind- and water-resistant, recycled Atmos™ fabric. The bag has a narrow mummy shape to minimise bulk, lightweight zips and pullers, and comes with a lightweight, waterproof, roll-top compression sack for protection from the elements and a small pack size while on the move.

The trapezoid boxwall baffle construction allows the down to fully loft, eliminates cold spots, and maximises warmth. It has an additional, adjustable baffle around the neck and an internal baffle along the length of the zip, both designed stop the heat from escaping. Hand-filled in the UK, all our down bags benefit from never having had their down compressed before use, maintaining the down’s loft and warmth.

  • Weight:925g/32.6oz
  • Insulation:900FP European Goose Down with Nikwax Fluorocarbon-Free Hydrophobic Finish (600g / 21.2oz)
  • Main Fabric:10D Recycled Atmos™ (27gsm) with Fluorocarbon-Free DWR
  • Fabric Lining:Lining: 10D Recycled Atmos™ (27gsm) with Fluorocarbon-Free DWR
  • EN (13537:2012) Temperature rating:ISO EN: Comfort: -5°C (23°F), Limit: -12°C (10°F), Extreme: -32°C (-26°F)
  • Rab Sleep Limit:-12°C / 10°F
  • Packed Size:40cm x 26cm (15.7in x 10.2in)
  • Product Code:QSI-46
  • Weight saving chevron baffle design, reduces down migration and optimises core warmth.
  • Trapezoidal boxwall construction with differential cut, to maximise loft and warmth
  • Close fitting adjustable neck baffle design for decreased heat loss
  • YKK® 3/4 length main zip with synthetic filled baffle to trap warmth
  • YKK® zipped internal stash pocket
  • Angled foot box for relaxed sleeping posture
  • Anti snag internal zip guard
  • Lightweight waterproof roll-top compression sack included

Sleeping Bag Size Guide

Tapered Mummy Regular
Sleeping Bag Length 215cm / 84.6in
Max User Height 185cm / 72.8in
Internal Shoulder Girth 160cm / 63.0in
Internal Hip Girth 134cm / 52.8in
Internal Foot Girth 102cm / 40.2in
Pack Size 40cm x 26cm


Material facts

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Material Facts

Mythic 600 Down Sleeping Bag (-12C)

Total Recycled Content*  31%
Fabric  100%
Hydrophobic Down 0%
Zips  37%
Trims  8%
Fluorocarbon Content 
Fabric  No
Hydrophobic Down No
Zips  Yes
Trims No
Manufactured in United Kingdom
*Calculations based upon the weight of a regular length sleeping bag.
QSI-46 Version 09/2023