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Gear Question
Does the down quality really affect how warm the bag is? If one...
By Spencer Buchanan
July 17, 2008
Does the down quality really affect how warm the bag is? If one is 15 degree and 600 fill, does that make a difference for the 800 fill one?
View Details: Big Agnes Mystic SL Sleeping Bag: 15 Degree Down
Helpful Votes: 0 Yes
By dalday
January 14, 2011
this is a great explanation of fill power from Jeff here Spencer. But just to clarify fill power is the number of cubic that one ounce of down will occupy in a controlled environment(in³/oz). There are several ways that companies test this and come up with these numbers but as far as the benefits of a higher fill power, Jeff is right on!
Helpful Votes: 0 Yes
By moroni
Ranked #7 - 25 to 5 Degree Down Bags
October 29, 2008
It makes a difference in the weight. 800 fill means that one ounce of down fills up 800 cubic centimeters, whereas 600 would be 600 cubic centimeters. So the higher number actually means that less down is used to obtain the same warmth, because it is a higher quality down that fills more for its weight, making the bag lighter. Or alternatively, if the same weight of down were used, the higher quality down (800 fill) would be warmer because it would have that extra 200 cubic centimeters of insulation per ounce.All down traps air. This is how it insulates. The higher fill power e.g. 750, 800, 850, etc. has more to do with compressibility. Now your sleeping bag has a lower temperature range & weighs less.
Helpful Votes: 0 Yes
Tech Specs:
- Material:
- [Shell] Toray (ultralight ripstop nylon) with DWR; [Lining] nylon taffeta
- Insulation:
- 800-Fill down
- Shape:
- Squared-off mummy
- Draft Collar:
- Yes
- Max User Height:
- [Reg] 5ft 10in (178cm); [Lng] 6ft 6in (198cm)
- Shoulder / Hip / Foot Circumference:
- [Reg] 70 / 66 / 54in (178 / 167.6 / 137cm); [Lng] 73 / 69 / 55in (185.4 / 175.3 / 140cm)
- Stuff Size:
- [Reg] 8 x 5in (20.3 x 12.7cm); [Lng] 8 x 6in (20.3 x 15.3cm)
- Stuff or Storage Sack:
- Both
- Degree:
- 15F (-9C)
- Weight:
- [Reg] 2lb 7oz (1106g); [Lng] 2lb 10oz (1191g)
- Recommended Use:
- Spring through autumn camping & backpacking
- Manufacturer Warranty:
- Lifetime
- Country of Origin:
- China
Change me.



