Premium pick
Images: Rab and its retailers. Used for product identification.
Rab
Rab Neutrino -6 °C
Rab's hand-filled 800 FP classic, now named by temperature: 0 °C comfort at 870 g.
- Weight
- 870 g
- Comfort
- 0 °Climit -6 °C
- Packed
- 18 × 30 cm
Best price found
£401.76
at Alpinetrek · In stock, some sizes sold out · RRP £489.95
Prices checked 31 October 2026. We may earn a commission on these links.
- 800 FP down
- Hydrophobic down
- Recycled fabrics
Specifications
- Weight
- 870 g (successor to the Neutrino 400)
- Packed size
- 18 × 30 cm
- Comfort
- Comfort 0 °C / limit -6 °C
- Fill
- 800 FP goose down, 400 g fill
- Shell & construction
- 10D Pertex Quantum ripstop on top; L.O.F.T 3D helix-shaped baffles with longitudinal…
- Rating Standard
- ISO 23537 rating
- Fill Note
- 800FP European goose down with Grangers fluorocarbon-free hydrophobic finish.…
- Zip
- Two-way YKK anti-snag zip with insulated zip baffle
Pros & cons
- Excellent warmth-to-weight ratio and highly packable; 5/5 stars
- High-quality materials, effective anti-snag zip, waterproof compression stuff sack
- Tried-and-tested design in several sizes with decent sustainability credentials
- Close, tapered mummy fit may not suit everyone
- Expensive at £470 RRP; LFTO scored value 3.5/5 on the predecessor
More down bags
Full comparison →
11 photosBest valueAlpkit
Alpkit PipeDream 400
Hydrophobic 750 FP RDS down with a -4 °C comfort rating for under £300, direct from Alpkit.
- Weight
- 770 g
- Comfort
- -4.2 °Climit -10.8 °C
- Packed
- 25 × 18 cm
- 750 FP down
- Hydrophobic down
- RDS down
- 160 cm zip
- Draught collar
Full specs, 1 retailer →View DealFrom
£274.99
at Alpkit
11 photosBest all-rounderMountain Equipment
Mountain Equipment Helium 400
The 3-season benchmark: 0 °C comfort at 820 g, widely stocked and often discounted.
- Weight
- 820 g
- Comfort
- 0 °Climit -6 °C
- Packed
- 24 × 21 × 20 cm
- 700 FP down
- RDS down
- Recycled fabrics
- Box-wall baffles
Full specs, 3 retailers →View DealFrom
£240
at Trekitt
Lightest for warmthCumulus
Cumulus Panyam 450
Polish-made 850 FP goose-down bag that undercuts the big brands; ships from Poland.
- Weight
- 810 g
- Comfort
- 0 °Cbrand's own figure
- Packed
- 26 × 18 cm, 6 L
- 850 FP down
- Box-wall baffles
- Two-way zip
Full specs, 1 retailer →View DealFrom
£289
at Cumulus

