NEMO's Disco 15 is a sleeping bag worth buying for people who drive to places with a lowest temperature down to −3°C. The comfort temperature is −3°C, the minimum weight 1.23kg, and the official price JPY 31,900 incl. tax. The 15 in the name is not a temperature guide, so choose by the comfort temperature in the spec table.
The Gear Nerd's Pick
If you cannot choose between the Disco 30 and 15, buy the 15. The 15 is 350g heavier than the 30, but 322g of that is down, and fabric and parts add only 28g. The JPY 5,500 difference is almost money for filling. On a hot night you just open the thermal gill at the chest, so I carry the warmer one.
Key points
- The gap between comfort and limit temperature is 6°C. The 15 converted from Fahrenheit to Celsius is −9.4°C, which overlaps the limit temperature of −9°C
- Price per gram of down is JPY 49.7, about 60% of the Disco 30's JPY 82.5
- At the same comfort −3°C, it is 312g heavier than the mont-bell Seamless Down Hugger 800 #1, with about 1.6 times the packed size. In exchange it is JPY 12,900 cheaper
In this article (7 sections)
- NEMO Disco 15's comfort temperature is −3°C: how it differs from the 15 in the name
- How I judged it
- Difference from the Disco 30: 322g of the added 350g is down
- What I like: a spoon shape that lets you bend your knees, and a build that lets heat out
- Things to watch: 312g heavier than a mummy type with the same comfort −3°C
- Who is it for?
- FAQ
NEMO Disco 15's comfort temperature is −3°C: how it differs from the 15 in the name
The Disco 15 is a buy for people who drive to places with a lowest temperature down to −3°C.
Watch the name. The “15” in Disco 15 is neither 15°C nor −15°C. 15 converted from Fahrenheit to Celsius is −9.4°C ((15 − 32) × 5 ÷ 9), a number that overlaps the spec table's limit temperature of −9°C.
The guide for sleeping stretched out is the other number, the comfort temperature, which is −3°C. The two differ by 6°C.
| Item | Official numbers |
|---|---|
| Comfort temperature | −3℃ |
| Limit temperature | −9℃ |
| Minimum weight | 1.23kg |
| Packed size | 29×φ21cm |
| Filling | 650FP water-repellent down, 642g |
| Size | Regular only (for heights up to 183cm) |
| Official price | JPY 31,900 (incl. tax) |
Whether to choose by comfort temperature or limit temperature is covered in the article that subtracts the difference across 15 sleeping bags.
How I judged it
The first thing I looked at was not the 15 in the name but the comfort temperature of −3°C in the spec table. Compared with the Disco 30, the price per gram of down fell from JPY 82.5 to JPY 49.7.
What I wavered on was weight. It is 312g heavier than mont-bell's mummy type at the same comfort −3°C, and about 1.6 times the packed size. I still recommend it because if you carry by car, the trunk takes the weight, while the JPY 12,900 lower price and a shape you can sleep in with bent knees remain. It suits side sleepers who want one bag for autumn and winter.
Difference from the Disco 30: 322g of the added 350g is down
| Item | Disco 30 | Disco 15 | Difference |
|---|---|---|---|
| Comfort temperature | 4℃ | −3℃ | 7℃ |
| Limit temperature | −1℃ | −9℃ | 8℃ |
| Minimum weight | 880g | 1,230g | +350g |
| Down fill | 320g | 642g | +322g |
| Packed volume | About 6.5L | About 10.0L | + about 3.5L |
| Official price | JPY 26,400 | JPY 31,900 | +JPY 5,500 |
| Per gram of down | JPY 82.5 | JPY 49.7 | -JPY 32.8 |
What increased is the filling. 92% of the added weight is down (322 ÷ 350), and the rest, fabric, zipper and hood, grew by only 28g. The price per added gram of down is about JPY 17.1 (5,500 ÷ 322). That is cheap for adding warmth.
The Disco 30 is for: people who stay from spring to autumn and whose lowest temperature does not drop below 4°C.
The Disco 15 is for: people who also go to lowlands from November to March, or high-altitude campsites. It leaves 3°C of margin on a 0°C night.
What I like: a spoon shape that lets you bend your knees, and a build that lets heat out
Spoon shape: Your knees bend. In NEMO's explanation, only the elbow and knee positions are widened outward. The footbox keeps the same taper as a mummy type, and the maker says the outline takes a side-sleeping, knee-bent posture as is.
Thermo Gill: A port that lets heat out. It is a vent at the chest, and how you open the double zipper lets only the heat escape. When you spend more than half the year camping, you take one sleeping bag out on 5°C nights and −3°C nights alike, so I give the build that lets heat out the same weight as the warmth number.
The footbox fabric is waterproof breathable. The down is also water-repellent treated. It anticipates the scene where your feet touch the tent wall on a winter morning and get wet.
Things to watch: 312g heavier than a mummy type with the same comfort −3°C
This part is a weak point. The mont-bell Seamless Down Hugger 800 #1 at the same comfort −3°C is 918g, about 6.4L and JPY 44,800, and the Disco 15 is 312g heavier with about 1.6 times the packed size.
I read it as the down being 650FP against 800FP, so more is needed for less lofting power. The choice is whether to pay about JPY 41 to save 1g (12,900 ÷ 312): people who walk with it on their back pay, and people who carry by car do not.
The mat matters too. A sleeping bag's temperature changes with the mat you lay under it. If you use it in winter, look at the mat's R-value as well. If you are thinking about heating too, I also wrote the rules for using it inside a tent in the 50th anniversary oil stove review.
Who is it for?
It suits people who go by car and stay on nights down to a lowest temperature of −3°C. It also suits side sleepers who bend their knees, and people who found the knee area of a mummy type cramped.
If it is only lowlands from April to October, the Disco 30 is enough. People who walk with it on their back, go to places below −5°C, or are over 183cm tall should look at other sleeping bags too.
FAQ
What is the Disco 15 filled with?
It holds 642g of 650FP water-repellent down. FP is fill power, a number for the down's lofting ability.
Down to what temperature can the Disco 15 be used?
Down to −3°C if you sleep stretched out. The official comfort temperature is −3°C and the limit temperature is −9°C, and I do not bring it on days when the forecast is colder than that.
Disco 15 or 30: which should I pick?
If you also stay in winter, 15. It is the 1 for people who also stay on nights when the lowest temperature falls below 4°C, and the difference from the 30 is 350g and JPY 5,500, with comfort temperature 7°C lower.
What changed in the Disco 15 from the previous model?
The official page lists a rework of the sleeping comfort and temperature regulation, and unifying the outer fabric to 100% PET.
Sources (5 official pages)
- NEMO Equipment Japan official store: Disco Men's Endless Promise 15
- NEMO Equipment Japan official store: Disco Men's Endless Promise 30
- NEMO Equipment Japan official store: list of sleeping bags
- mont-bell official online store: Seamless Down Hugger 800 #1
- mont-bell official: mont-bell sleeping bags (temperature rating explanation)
