Nemo
Nemo Riff -9 °C Endless Promise Down Sleeping Bag (Men's Regular)
Where it fits
- Also works for
- Backpacking and wild camping
- Not for
- Winter mountain
Why these labels
- Backpacking and wild camping: Light to carry: 1.1 kg
- Winter mountain: Comfort rating -2 °C: too cold for winter nights
From the maker's stated use and the published specs.
- Summer wild camp: 7/10 UK, roughly May to September, nights above about 8 °C, sheltered pitches.
- Three-season hills: 7/10 UK hills in spring and autumn. Wind, rain, and nights near freezing.
- Winter camp: 4/10 UK winter or high ground. Below freezing, strong wind, possibly snow. Capped at 4: needs warmth 9+ (comfort -5 °C or colder).
- Weight: 6/10 How much it adds to your pack, compared with the whole market.
Comfort -2 °C, limit -8 °C (ISO 23537).
Side sleepers and restless sleepers who want a down bag without a tight mummy cut
- Comfort
- -2 °C
- Limit
- -8 °C
- Fill
- 800 fill down
- Weight
- 1.12 kg (Regular)
Packed size 6.2 L, 29 cm long and 19 cm across Compare with a 2-litre bottle
About as long as a 2-litre bottle and about twice as wide. Drawn to scale.
Where to buy
Ultralight Outdoor Gear £339.99 In stock. Free delivery. Only 1 in stock when checked.
View at shop: Ultralight Outdoor GearAbsolute Snow £399.95 Out of stock. Shop page says currently unavailable.
View at shop: Absolute SnowAlpinetrek £299.96 Out of stock.
View at shop: AlpinetrekPrices checked 8 Nov 2026 on each shop's own page; shops can change them. We earn no commission on these links; shops are listed by price. More
Our ratings (out of 10)
1 to 10, compared with the whole market. Each says what it's based on. How we score
Warmth
From maker's figures 7/10How cold a night you can sleep comfortably through. 7: Better than most.
Nemo's ISO comfort figure of -2 °C sits in the -4.9 to 0 °C band; the limit is -8 °C. Despite the 15 in the name, it is a three-season bag.
Room inside
Estimate: only 2 reviews about room inside (fewer than the 3 we need, so never above 8) 8/10How much room to move, bend your knees and sleep on your side. Roomier is comfier. 8: Clearly better than most.
The Riff's spoon shape gives extra space at the elbows and knees, and reviewers say it suits side sleepers. It stays a tapered bag, so it is roomy for its type rather than a wide bag.
Weight
From maker's figures 6/10How much it adds to your pack. 6: A bit better than average.
Nemo's minimum weight of 1.12 kg sits in the 1,000–1,299 g band.
Packed size
From maker's figures 6/10How much room it takes in your rucksack. 6: A bit better than average.
Nemo states a compressed volume of 6.2 L, in the 6–8.9 L band.
What reviewers say (out of 10)
Ratings marked * are from reviews and are not part of the trip score. They are reviewers' scores, not our own measurements. How we score
Comfort to sleep in*
Estimate: only 1 review about comfort to sleep in (fewer than the 3 we need, so never above 8) 8/10How comfy the shape, hood and fabric feel; not the temperature rating.
1 review on comfort to sleep in, e.g. "Very comfortable for a mummy bag.".
In short
Good for
- Side sleepers and restless sleepers who want a down bag without a tight mummy cut
- Three-season UK camps where you need to cool down as well as keep warm
- Backpackers who value comfort features over the last few hundred grams
Strengths
- Spoon shape gives extra room at the elbows and knees, praised by UKHillwalking
- Thermo Gill vents let you cool down without opening the main zip
- Waterproof, breathable hood and footbox keep tent condensation out of the down
- 1.12 kg and 6.2 L packed for a -2 °C comfort bag
Weaknesses
- The 15 in the name is not the comfort figure: ISO comfort is -2 °C
- Heavier than ultralight down bags with a similar comfort figure
- Shoulder girth is 152 cm and hip girth 135 cm, slimmer than the 157 and 145 cm of the Therm-a-Rest Parsec
- Only one independent review covers the men's bag
Sources
We haven't tested this ourselves. Every score comes from these specs, tests and reviews.
ShowHide sources (6)
- Nemo: Riff Men's Endless Promise Down Sleeping Bag, Regular specifications (US site)
- UKHillwalking: Nemo Sleep System review
- Better Trail: Nemo Riff 15 sleeping bag review
- Mountains for Everybody: Nemo Riff review
- UKC/UKHillwalking: Nemo Sleep System review (Riff 15, Tensor Trail, Fillo King)
- Mountains for Everybody: NEMO Riff 15 Degree Sleeping Bag