Summer ultralight
Images: Mountain Equipment and its retailers. Used for product identification.
Mountain Equipment
Mountain Equipment Helium Solo
Mountain Equipment's lightest bag at 420 g, rated comfort 16 °C for summer trips, from £150.
- Weight
- 420 g
- Comfort
- +16 °Cbrand's own figure
- Packed
- 22 × 11 × 11 cm (retailer figure; not stated by maker)
Best price found
£149.96
at Alpinetrek · In stock · RRP £199.95
- TrekittRRP £210.00£157.50View Deal
- Ultralight Outdoor GearIn stock · RRP £199.99£169.99View Deal
- Mountain EquipmentIn stock, some sizes sold out · Some sizes sold out · Direct from maker£210View Deal
Prices checked 31 October 2026. We may earn a commission on these links.
- 700 FP down
- RDS down
- Recycled fabrics
- Shaped foot box
- Under 450 g
Specifications
- Weight
- 420 g (regular; Long 422 g (UOG))
- Packed size
- 22 × 11 × 11 cm (retailer figure; not stated by maker)
- Comfort
- Comfort +16 °C / limit +13 °C
- Fill
- 700 FP duck down, 134 g fill
- Shell & construction
- Outer: recycled HELIUM 20D, PFAS-free DWR. Lining: recycled Supersoft 20D; stitch-through top and base
- Rating Standard
- Standard not stated by maker
- Fill Note
- 90/10 pure duck down, RDS certified with DOWN CODEX traceability. Maker's 'Good Night's Sleep' figure is 7 °C; Alpinetrek lists older 14 °C / 10 °C ratings.
- Season
- Summer
- Zip
- Side zip (UOG lists 3/4 length)
Pros & cons
- At 420 g UOG rates it 'one of the lightest sleeping bags available'
- UOG praises the 'excellent sculpted footbox' and built-in neck collar
- Often under £160 at UK retailers
- 16 °C comfort rating means warm summer nights or huts only in the UK
- Stitch-through build and a simplified hood trade warmth for weight
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
