90% down 10%

[Ramblinrev]

Duck down is a very inferior product to goose down. Whether that would make it unusable for your application is a choice only you can make.

[Violent Green]

it does say 90% down 10% feather and it is also white duck down. So this should be ok. I will only be using it to -3oc and no lower

It will definitely keep you warm. The only question is how much down will it take to keep you warm at the temperatures you will experience. You don't see high fill power duck down typically, and it isn't as efficient as goose down. I think 700fp is the highest I have ever seen & not a good chance you will see that in a pillow or blanket. Who knows though.

If weight or cost isn't a factor in your decision - I would treat it like it was 550-600 fill power down and fire away.

Ryan